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BIO- AND NANO MATERIALS

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Nanocarbon electrochemistry and interfaces II

This symposium will focus on electrochemical and interface properties of carbon and carbon- related materials (e.g., diamond, CNTs, graphene, carbon particles, and composites, etc). The key topics will include their application for electroanalysis, biosensing, electrocatalyst, electrosynthesis, energy storage and conversion, etc.

Scope:

Following by the successful symposium held in 2015, this symposium will continuously focus on the electrochemistry and interfaces based on nanocarbons, including novel carbon films (e.g. conductive diamond, fullerenes, DLC, CNTs, graphene, etc.), carbon nanoparticles (e.g. diamond nanoparticles, carbon dots, carbon powders, graphene dots, etc.) and micro-fabricated and CVD grown carbon structures (e.g. carbon foam, diamond nanowires, porous diamond, carbon nanofibers, etc.) as well as carbon nanocomposites (e.g. diamond/SiC nanocomposite films, carbon nitrite, etc.). The topics with respect to the growth and electrochemical characterization of these novel carbons in different media as well as their interfacial properties will be covered. The relationships between the carbon bulk structure, electronic properties and surface chemistry with their nanostructures for different electrochemical and interface applications will be contained. Of particular focus will be the applications of these nanocarbons for electroanalysis, biosensing, electrocatalytic reactions, electrosynthesis, environmental degradation, and energy storage and conversion. In vivo and in vitro electrochemical sensing with novel carbons, electrocatalytic electrochemical performance will be included. The generation of various carbon reactions (e.g., hydrogen evolution reaction, oxygen reduction reaction, CO2 reduction reactions) using carbocatalysts, organic synthesis using diamond electrodes, electrochemical-photochemical degradation of environmental pollutants as well as supercapacitors/batteries from carbon nanomaterials are the main hot topics in the symposium. The fabrication, characterization, and application of micro and nanostructured carbon materials for electrochemical devices and setups (e.g., scanning probe microscopes) and spectroelectrochemistry (e.g., transparent electrodes), the novel nanocarbons for single molecular detection such as DNA sequencing using graphene nanopores will be highlighted.

Hot topics to be covered by the symposium:

  • Simulation of carbon nanoelectrochemistry
  • Carbocatalysts for water splitting 
  • Carbocatalysts for CO2 reduction
  • Nanocarbon for supercapacitors
  • Nanopcarbon for batteries
  • Nanocarbon for single molecule detections
  • Electrosynthesis using diamond electrodes
  • Electrocatalysts on nanocarbon electrodes
  • Nanocarbons for in-vivo electrochemistry
  • Nanocarbon interfaces for sensing
  • Nanocarbon based electrochemical devices                                                                         

Tentative list of confirmed invited speakers:

  • Hua Zhang (Nanyang Technological University, Singapore)
  • Robert Hamers (University of Wisconsin-Madison, USA)
  • Gregory F. Schneider (Leiden University, Netherlands)
  • Wenjun Zhang (City University of Hongkong, China)
  • Philippe Bergonzo (CEA, France)
  • Teruhiko Matsubara (Keio University, Japan)
  • Osamu Niwa (Saitama Institute of Technology, Japan)
  • Franceso Paolucci (University of Bologna, Italy)
  • Robert Dryfe (The University of Manchester, UK)
  • Paula Colavita (Trinity College Dublin, Ireland)
  • Xiaodong Zhuang (Technische Universitaet Dresden, Germany)
  • Anke Krügel (University of Würzburg, Germany)
  • Alfred Tok Iing Yoong (Nanyang Technological University, Singapore)
  • Chen Wei (National University of Singapore, Singapore)
  • Zijian Zheng (The Hong Kong Polytechnic University, China)
  • Quan Xie (Dalian Institute of Science and Technology, China)
  • Oliver A. Williams (Cardiff University, UK) 

Selected papers will be published at Journal CARBON (https://www.journals.elsevier.com/carbon/).
The submission deadline is Oct. 1st and Paper type is "VSI: NanoC for Electrochem.

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08:50 Opening Remarks    
 
Plenary Session : Nianjun Yang
09:00
Authors : Hua Zhang
Affiliations : Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore

Resume : In this talk, I will summarize the recent research on two-dimensional nanomaterials in my group. I will introduce the synthesis and characterization of novel low-dimensional nanomaterials and their hybrid nanomaterials. Then I will demonstrate the applications of these novel nanomaterials in chemical and bio-sensors, water remediation, (electro-)catalysis, clean energy, etc.

V.1.1
09:30
Authors : Robert J. Hamers
Affiliations : University of Wisconsin-Madison

Resume : Diamond is widely known to be an excellent electron emitter in vacuum, in recent year we have been investigating the use of illuminated diamond as a solid-state source of electrons that can function in non-aqueous environment, including water and ambient gases. In water, electrochemical reactions outside the stability limits of water are extraordinarily difficult to achieve because reduction of H to H2 is normally facile. However, by directly ejecting electrons directly in water, diamond enables investigation of more extreme species such as the solvated hydrogen atom and the solvated electron. These potent reducing agents induce a wide range of novel chemical reactions, including reduction of N2 to NH3 and reduction of CO2 to CO. One of the challenges of working with diamond is that it has poor optical absorption even above using above-bandgap excitation. To circumvent this, we have bene investigating the use of diamond-metal heterostructures and embedded plasmonic nanoparticles. The use of these methods can enhance above-bandgap response and initiate sub-bandgap photocatalytic properties. in this talk I will highlight some of the properties of diamond that lead to its unique properties, and how the formation of diamond-metal heterostructures can help overcome some of the inefficiencies associated with diamond's weak optical absorption. We have also explored the photocatalytic properties of diamond nanoparticles and how they compare with planar diamond films. These studies show that diamond nanoparticles dispersed in water can also be effective photocatalysts, provided suitable attention is paid to replenishing the valence-band holes by using a suitable electron donor in solution.

V.1.2
10:00
Authors : Grégory F. Schneider
Affiliations : Universiteit Leiden

Resume : DNA sequencing with graphene: chemistry comes first! Grégory F. Schneider Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333CC, Leiden, The Netherlands DNA sequencing and biomolecular sensing are among the most envisioned applications of graphene, nonetheless each step towards these targets faces important challenges. In order to succeed, our research exploits chemistry: from the synthesis of graphene to handling, functionalization and application for graphene sensing devices. Remarkably, we recently introduced an innovative mixed cold/hot walls synthesis for CVD graphene and developed bottom-up 2D organic films from polycyclic aromatic hydrocarbons structured by self-assembly as a network of molecularly precise nanopore arrays. Furthermore, we implemented polymer free transfer methods based either on the biphasic caging of graphene using cyclohexane or lipidic clamps, ensuring the highest quality films notably free of polymer residuals. Among the most relevant advantages are, for instance, TEM imaging, nanofabrication, transport and bionics. Furthermore, we implemented graphene heterostructures based on hydrogels and graphene-lipid superstructures aiming at rendering graphene more compatible with membrane proteins and/or hydrophilic. Our unique chemical tools were further employed to investigate the chemical functionalization of graphene via hydrogenation and through the electrografting of diazonium salts, particularly with an outlook for novel biosensing schemes, understanding the interplays between electrochemistry and quantum transport, both in terms of molecular selectivity and sensitivity of next generations of graphene field effect transistor sensors. Also, we investigated the surface chemistry and interfacial properties of graphene studying the wetting transparency and hydrophilicity of graphene, with a particular focus on the interaction of graphene with biomolecules such as proteins, aiming to understand the impact of water ? conferring hydrophilic characteristics to graphene when suspended in water ? on how graphene sensors in water operate (most particularly nanopores and nanogaps). All these results now deserve the fabrication of the first dynamic tunneling graphene nanogap at the intersection of two single carbon atoms lying on the edges of graphene which are used to detect single nucleotides and high sensitivity graphene sensors capable of detecting single molecules of ethane or to monitor the magnetic phases transitions within organometallic crystal complexes. To conclude, we believe that chemistry will play an increasingly larger role in the design of the next generation of graphene technologies. Literature: 1. Arjmandi-Tash, H., Belyaeva, L. a & Schneider, G. F. Single molecule detection with graphene and other two-dimensional materials: nanopores and beyond. Chem. Soc. Rev. 45, 476?493 (2015). 2. Arjmandi-Tash, H., Lebedev, N., van Deursen, P. M. G., Aarts, J. & Schneider, G. F. Hybrid cold and hot-wall reaction chamber for the rapid synthesis of uniform graphene. Carbon N. Y. 118, 438?442 (2017). 3. Belyaeva, L. A., Fu, W., Arjmandi-Tash, H. & Schneider, G. F. Molecular Caging of Graphene with Cyclohexane: Transfer and Electrical Transport. ACS Cent. Sci. 2(12), 904-909 (2016). 4. Lima, L., Arjmandi-Tash, H. & Schneider, G.F. Clamping graphene from the edges using a non-covalent lipid molecular scaffold [Submitted]. 5. Lima, L., Fu, W., Jiang, L., Kros, A. & Schneider, G. Graphene-stabilized lipid monolayer heterostructures: a novel biomembrane superstructure. Nanoscale 8, 18646?18653 (2016). 6. Jiang, L., Fu, W., Birdja, Y. Y., Koper, M. T. M. & Schneider, G. F., Quantum and electrochemical interplays in hydrogenated graphene [submitted] 7. Bellunato, A. & Schneider, G. F. Electrografting of 4-nitrobenzene diazonium on ultrasmooth graphene edge electrodes [Submitted]. 8. Belyaeva, L. A., van Deursen, P. M. G., Barbetsea, K. I. & Schneider, G. F. Hydrophilicity of free-floating graphene on water [Submitted]. 9. Bellunato, A., Vrbica, S., Sabater, C., Van Ruitenbeek, J. & Schneider, G.F. Dynamic tunneling junctions at the atomic intersection of graphene edges [Submitted]. 10. Fu, W., van Dijkman, T. F., Lima, L. M. C., Jiang, F., Schneider, G. F. & Bouwman, E. Tracking fluctuations of dipole moments during a chemical reaction [Submitted]. 11. Bellunato, A., Arjmandi Tash, H., Cesa, Y. & Schneider, G. F. Chemistry at the Edge of Graphene. ChemPhysChem 17, 785?801 (2016). 12. Fu, W., Jiang, L., van Geest, E. P., Lima, L. M. C. & Schneider, G. F. Sensing at the Surface of Graphene Field-Effect Transistors. Adv. Mater. 29, 1603610 (2017).

V.1.3
10:30 Coffee break    
11:00
Authors : Zijian Zheng*, Haoli Zhang
Affiliations : 1. Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong SAR, China 2. State Key Laboratory of Applied and Organic Chemistry, Lanzhou University, Lanzhou, China

Resume : Wearable electronics is foreseen to be the next major technology after smart phone in the near future. However, most conventional electronic devices are rigid, bulky, and heavy, making them difficult to wear. On the other hand, textiles are materials that have been worn by human beings for more than a thousand years. Textiles are comfort, lightweight, conformal, and highly manufacture-able. This talk will introduce how our research group makes use of textiles for wearable electronics. These textile-based electronic devices can function as high-performance electronics while maintaining the flexibility, lightweight, permeability, processibility, and even washing ability like textiles. [1] Q. Huang, D. Wang, Z. J. Zheng*, Adv. Energy Mater. 2016, DOI: 10.1002/aenm.201600783. [2] L. Liu, Y. Yu, C. Yan, K. Li, Z. J. Zheng*, Nat. Commun. 2015, 6, 7260. [3] Y. Yu, C. Yan, Z. J. Zheng*, Adv. Mater. 2014, 26, 5508­5516. [4] Y. Yang, Q. Huang, L. Niu, D. Wang, C. Yan, Y. She, Z. J. Zheng*, Adv. Mater. 2017, 1606679.

V.11.2
11:30
Authors : Xiaodong Zhuang,* Xinliang Feng
Affiliations : Dresden University of Technology, Mommsenstr. 4, 01069 Dresden, Germany E-mail: xiaodong.zhuang@tu-dresden.de

Resume : Porous carbons have attracted tremendous attention from both science and industry communities due to its wide applications for energy storage and conversion. Surface area, dopants and dimensionality have been recognized to be the three main features rendering the performance of porous carbons. However, the rational synthesis of porous carbons with controlled porosity, heteroatom dopants and dimensionality still remain great challenge. Porous polymers, which are one kind of rising porous carbon precursors, can rational synthesized at molecular level due to the widely commercial available and designable heteroatom-containing monomers and different high yield polymerization methods. Most importantly, the dimensionality can be controlled by using nanocarbons with different dimensionalities, e.g. quasi-zero-dimensional carbon sphere, one-dimensional carbon nanotube and two-dimensional graphene, without removing templates. In this presentation, the energy related applications of porous polymers derived porous carbons will be introduced, e.g., as electrodes for supercapacitors, as electrocatalysts for oxygen reduction reaction and as air-cathodes for Zn-air batteries.

V.2.2
12:00
Authors : Luca Bettini, Andrea Bellacicca, Paolo Piseri, Paolo Milani
Affiliations : CIMaINa and Dipartimento di Fisica, Università degli Studi di Milano, via Celoria 16, 20133 Milano, Italy

Resume : Paper is a lightweight and renewable material with high applicative interest as substrate for flexible electronics. The integration on paper of porous electrodes is necessary for the fabrication of paper-based energy storage devices and requires the development of coating techniques compatible with fragile substrates, e.g. paper. Supersonic Cluster Beam Deposition (SCBD) is an additive technology based on the production of intense nanoparticle beams enabling the high throughput integration of nanostructured materials on almost any substrate, including polymers [J Phys D: Appl Phys 2006, 39, R439]. The assembling of carbon nanoparticles via SCBD is a promising method with validated usability for the growth of carbon thin films with structural properties that are beneficial for electrochemical applications requiring highly porous electrodes. The deposition of carbon thin films at room temperature and in clean high-vacuum conditions, as typical of SCBD, discloses novel opportunities within the general issue of the integration of porous carbon into electrochemical systems [J Power Sources 2016, 326, 717]. We report the fabrication of planar microsupercapacitors where carbon electrodes are deposited by SCBD on paper sheets and ionic liquids are used as electrolyte. As prepared devices exhibit energy storage performances that are consistent with the requirements of paper-based microelectronic platforms, such as sensors and biomedical devices [Flex Print Electron 2017, 2, 025002].

V.2.3
12:15
Authors : Daniel Arenas-Esteban, Amalia Ode-Fernández, David Ávila-Brande, L. Carlos Otero-Díaz
Affiliations : Department of Inorganic Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E?28040, Madrid, Spain.

Resume : Electrical double layer capacitors (EDLC) have a large power density which allow to store energy faster than a battery, unfortunately, they have lower energy density than a regular battery. Supercapacitors are called to be the meeting point between capacitors and batteries, reaching both high power and energy density. Starting from the double layer capacitance mechanism, where the charged surface area interacts electrostatically with the ions present in the electrolyte, to improve their energy density trough different strategies. In first place, the use of high surface area materials, the larger the surface area is the greater the energy that could be stored. Activated carbon materials are the most used materials on EDLC in this sense, besides having a low cost and environmental friendly. Otherwise would be take advantage of the fast and reversible surface redox reaction that take place on metal oxides which have cations with different states of oxidation available to store energy through a different mechanism that for similarity with the previous one is called pseudo-capacitance. In this work, different composite materials based on activated nutshell carbons of high surface area (~ 2.900 m2/g) filled with increasing concentration of manganese oxide nanoparticles has been synthetized and their electrochemical performance as an electrode material for supercapacitors have been evaluated. The electrochemical characterization is focused on how this two different mechanism can work together on a composite material providing high capacitance values per mass, area or volume.

V.2.4
12:30 Lunch break    
 
Biosensing : Gregory Schneider
14:00
Authors : Alfred Tok, Myra Nimmo, Bo Liedberg
Affiliations : Alfred Tok (Nanyang Technological University, Singapore); Myra Nimmo (University of Birmingham, UK); Bo Liedberg (Nanyang Technological University, Singapore).

Resume : The monitoring of various physiological biomarkers can be an important tool in the training and performance of athletes. These biomarkers can be found in a whole host of body fluids, ranging from sweat, tears, blood and urine etc. During exercise, sweating could lead to the loss of electrolytes such as sodium and potassium. Sodium levels in sweat could be used to ensure adequate Na+ replenishment in order to prevent exercise-associated hyponatremia. Therefore, sodium measurement in sweat was important and essential for hydration status and was commercially important for the production of rehydration drinks. Another physiologically important aspect is the sensing of biomarkers via sweat. For example, Interleukin-6 (IL-6) is a multi-functional cytokine with a wide range of biological activities such as regulation of the immune system and generation of acute phase reactions. IL-6 also plays a key role in metabolism during exercise. IL-6 is predominantly produced within the working skeletal muscles during exercise. IL-6 circulation levels were also found to increase in response to acute exercise in young males and can be modulated by acute bout of high-intensity intermittent exercise in comparison to continuous moderate-intensity exercise (MOD). In this presentation, the characterisation, synthesis and sensing data of novel graphene-based biosensors are shown. They are disposable, organic, low-cost, and the sodium sensor has an added pump-integrated feature to transport fluids into the sensor. In order to increase the sensitivity of the sensor, various processing was done to increase the interconnectivity of the graphene sheets on the sensors, as well as increase the size of individual graphene flakes to increase conductivity. This integration allowed the sensor platform built to be small, portable and wearable; thus allowing the potential advantage to interface with the human body during field exercises enabling the provision of real-time data for immediate intervention. Both IL-6 and sodium sensors were able to detect to within the typical physiological range of human sweat.

V.3.1
14:30
Authors : A. Taylor1, P. Ashcheulov1, M. Davydova1, P. Hubík1, L. Klim?a1, Z. Reme?1, I. Dittert2, J. Kr??ek2, V. Benson3, Z. Vl?ková ?ivcová4, M. Remzová4, L. Kavan4, A.M. Beltrán5, J. Lorin?ík6, K. Schwarzová7 and V. Mortet1,3
Affiliations : 1Institute of Physics of the Czech Academy of Sciences, Prague, Czech Republic 2 Institute of Physiology of the Czech Academy of Sciences, Prague, Czech Republic 3Czech Technical University, Faculty of Biomedical Engineering, Kladno, Czech Republic 4J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Prague, Czech Republic 5Departamento de Ingeniería y Ciencia de los Materiales y del Trasporte, Escuela Técnica Superior de Ingeniería, Universidad de Sevilla, Sevilla, Spain 6Research Centre Rez, Husinec-?e?, Czech Republic 7Charles University, Faculty of Science, Department of Analytical Chemistry, UNESCO Laboratory of Environmental Electrochemistry, Prague, Czech Republic

Resume : Industrial application of high quality and heavily boron doped diamond, acknowledged as one of the best electrodes for electrochemical applications, is restricted by the limited coating area of MW deposition systems. Large area deposition of BNCD layers using a MW PECVD system with linear antenna delivery (MW-LA-PECVD) was reported in 2014 [1]. This synthesis is complicated by the addition of oxygen species, which are known to limit boron incorporation [2] and therefore reduce electrical conductivity in comparison with layers deposited using conventional MW systems. In this work, we study the effect of deposition conditions: CO2 concentration, B/O ratio, B/C ratio and deposition temperature, to synthesize high quality BNCD. Layers have been characterised by SEM, TEM, SIMS, Raman spectroscopy, optical transmission, Hall effect, XPS and cyclic voltammogram techniques. At optimal deposition conditions, BNCD layers are reproducibly deposited over large areas (dia. 20 cm) with low sp2 fraction and without formation of SiC parasitic phase. These layers show high electrical conductivity (> 35 S.cm-1) with high boron concentration (> 2×10 21 cm-3) and typical Raman features characteristic of BNCD with metallic conductivity. Finally, we will report on preliminary results of the use of such layers for monitoring of neuron electrical and chemical activity and will demonstrate scale up of porous diamond layers described in [3]. Ref.: [1] A. Taylor, DRM. 47 (2014) 27; [2] A. Taylor, PSS A 212 (2015) 2418; [3] Petrak, Carbon 114 (2017) 457-464 Acknowledgements: Czech Science Foundation contract No. 13-31783S and 17-15319S. J.E. Purkyne? fellowship awarded to V. Mortet by AS CR. Projects MEYS CR FUNBIO CZ.2.16/3.1.00/21568, LO1409 and LM2015088.

V.3.2
14:45
Authors : Bo Li, Aimin Yu, Guosong Lai
Affiliations : Hubei Normal University

Resume : A nonenzymatic glucose biosensing strategy was developed based on the electrochemical stripping analysis of gold nanoparticles (Au NPs) at a graphene/dextran modified electrode. The biosensor was prepared through the electrochemical reduction of graphene oxide modified on a screen-printed carbon electrode followed by further ?-? stacking of phenyl-dextran. Meanwhile, a gold nanoprobe was prepared through the concanavalin A (Con A) functionalization of Au NPs synthesized by the conventional citrate-reduction method. Upon mixing the glucose solution and Con A-functionalized Au NP nanoprobes for incubation reaction at the biosensor, the competitive recognition of Con A between glucose and dextran resulted in the quantitative capture of gold nanoprobes onto the electrode surface. Based on the electrochemical stripping analysis of the Au NPs, sensitive electrochemical signal was produced for the successful construction of a nonenzymatic glucose biosensor. This biosensor avoids the conventional use of glucose oxidase. The Con A biorecognition ensures the high selectivity of the method. The electrochemical stripping analysis of Au NPs excludes the conventional interferences caused by the higher or lower detection potentials. Besides, the graphene modification not only enables the simple preparation of the biosensor but also promotes its electrochemical response greatly. Thus this glucose biosensor with excellent performance indicates a great potential for practical applications.

V.3.3
15:00
Authors : Teruhiko Matsubara
Affiliations : Faculty of Science and Technology, Keio University

Resume : The modification of functional peptides on electrodes is an attractive conjugation for performing electrochemical detection. Functional peptides have been designed to perform electron transfer between proteins and electrodes through a redox group and to capture target proteins. Ferrocene- and anthraquinone-carrying polypeptides have been synthesized and electron transfer on these polypeptides has been investigated electrochemically. Short peptides that bind to the receptor-binding sites of viral proteins were recently identified by selection from a phage-displayed peptide library, and have been utilized to detect the influenza virus (IFV). A hemagglutinin receptor-mimic peptide was modified on a boron-doped diamond (BDD) electrode by click chemistry to detect IFV particles. The BDD electrode was used because of its excellent electrochemical characteristics such as its low background current and weak adsorption of proteins. Electrochemical impedance spectroscopy revealed that the peptide-modified BDD electrode was sufficiently sensitive to detect IFV in specimens. Regarding anti-influenza therapy, diagnosis at an early phase of infection before viral propagation is critical. Peptide-based biosensors have potential for clinical applications, and are expected to be useful for the future surveillance and prevention of IFV epidemics and pandemics.

V.3.4
15:30 Coffee break    
 
Catalysts I : Robert Hamers
16:00
Authors : Mai Tomisaki (1), Keisuke Natsui (1), Norihito Ikemiya (1), Yasuaki Einaga (1, 2)
Affiliations : (1) Department of Chemistry, Keio University, Japan; (2) JST-ACCEL, Japan

Resume : The electrochemical conversions of CO2 to useful compounds have been actively investigated. It is known that main products obtained by the electrochemical reduction of CO2 depend on electrodes. Sn, Hg, Pb, and In are known as electrodes on which formic acid is mainly produced, because these have high hydrogen overpotential. However, these are toxic, so the electrode which is environment-friendly and has high hydrogen overpotential is needed. Boron-doped diamond (BDD) is a suitable candidate, because it is a carbon-based electrode and has wide potential window compared with other electrodes in aqueous solutions. In this work, we investigated the electrochemical reduction of CO2 to formic acid on BDD, especially to find the appropriate electrolyte. Two compartment cell separated with Nafion was used for the electrolysis. We used BDD for working electrode, Pt for counter electrode and Ag/AgCl for reference electrode. 0.5 M MCl (M = Li, Na, K, Rb, Cs) aqueous solution saturated with CO2 was used for catholyte, and 0.5 M MOH aqueous solution was used for anolyte. The electrolysis was carried out at –2.0 mA/cm2 for 1 hour. The resuls showed that formic acid was mainly obtained. The faradaic efficiencies for the production of formic acid in LiCl, NaCl, KCl, RbCl, and CsCl solutions were 2.8%, 7.2%, 57%, 50%, and 42%, respectively. This is because the increase in pH near the electrode during the reduction is restrained using KCl, RbCl, and CsCl whose pKa for hydrolysis are small, indicating these act as buffer. Thus, the concentration of molecular CO2 which only undergoes reduction near the electrode is higher than that using LiCl and NaCl.

V.4.1
16:15
Authors : Halime Coskun1*, Abdalaziz Aljabour1,2, Phil De Luna3, Dominik Farka1, Theresia Greunz5, David Stifter5, Mahmut Kus2, Xueli Zheng4, Min Liu4, Achim W. Hassel6, Wolfgang Schöfberger7, Edward H. Sargent4, Philipp Stadler1, Niyazi Serdar Sariciftci1
Affiliations : 1Linz Institute for Organic Solar Cells, Institute of Physical Chemistry, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria 2Department of Chemical Engineering, Selcuk University, 42075, Konya, Turkey 3Department of Materials Science and Engineering and the 4Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, 10 King?s College Road, Toronto, Ontario M5S 3G4, Canada 5Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria 6Christian Doppler Laboratory for Combinatorial Oxide Chemistry (COMBOX) at Institute for Chemical Technology of Inorganic Materials, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria 7Institute of Organic Chemistry, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria

Resume : Anthropogenic-caused climate change drives the scientific demand towards the application of fossil fuel-free energy sources and thus the reduction and recycling of the CO2 emission. To date, noble metals play a crucial role in catalysis in terms of high energy yields, low overpotentials and satisfying selectivity, however the large scale utilization of those materials bring up limitations - as such the expense of metals. Here we report a complete bio-organic, non-metal electrocatalyst, that achieves notable performances comparable to best-in-class metal electrocatalysts. We conceptualize a vapor phase deposited naturally occurring pigment polydopamine (PDA), whose molecular structure combines hydrogen-bonds with a conjugated polyparaphenylene core. Only as such we are able to dope PDAs to achieve a threshold electrical conductivity in thin-film-based processing while preserving functionality to achieve a superior catalytic activity. We demonstrate CO2 reduction to formate and carbon monoxide at 18 mA cm-2 and 0.21 V overpotential and continuous operation for 16 h yielding at 80 % Faradaic efficiency. Hence our non-metal catalyst performs least on par with state-of-art formate-selective metals (e.g. 0.5 V for Ag at 18 mA cm-1).These results prove the importance of exploiting bio-originated templates as powerful catalytic centers for renewable and cost-efficient industrial CO2 reduction reaction.

V.4.2
16:30
Authors : Norihito Ikemiya, Keisuke Natsui, Kazuya Nakata, Yasuaki Einaga
Affiliations : Norihito Ikemiya;Keisuke Natsui; Yasuaki Einaga; Department of Chemistry, Faculty of Science and Technology, Keio University Kazuya Nakata;Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science

Resume : Over the several decades, many papers were reported on the electrochemical reduction of CO2 to valuable compounds using various kinds of metal electrodes. However, such metal electrodes sometimes include the toxic materials and have a high environmental load. In contrast to the metal electrodes, boron-doped diamond (BDD) electrode is highly stable in various acids and alkali-substances. BDD thin films were grown using a microwave plasma assisted chemical vapor deposition (MPCVD) system. The electrochemical experiments were performed in a two-compartment H-type cell (100mL). The constant current densities were applied for an hour. The products were analyzed by GC and HPLC. We have found that the extraordinary effect of Rb? cation compared with Na+, K+ and Cs+ cations on the electrochemical conversion of CO2 to formic acid using BDD electrodes. The Faradaic efficiency (FE) reaches 71 % for the formic acid production in 0.075 M Rb+ solution neutralized to 6.2 with HCl. For Cs+ solution, the FE reaches up to 38 % at maximum with 0.02M. The peaks of the FE stay around 0.5M, as for K+ and Na+ solutions. As for the K+ solution, the FE reaches 41% at best. In case of the Na+ solution, the FE stays at the lowest value of 24%. We discuss why Rb+ cation provides the good FEs for formic acid production. The 48-operation gives no damages on BDD electrode.

V.4.3
16:45
Authors : Mateusz Wlaz?o, Jacek A. Majewski
Affiliations : Faculty of Physics, University of Warsaw, Poland

Resume : Carbon reactions on graphene are of paramount importance across different fields. In chemical vapor deposition (CVD) reactor conditions, layers of graphene are grown from hydrocarbon precursors. Monolayer growth occurs directly on the substrate. Controlled bilayer growth is also possible, but the mechanisms of this process are unclear. Also, carbon nanostructures have great potential in removal and reduction of greenhouse gases, chiefly CO2. To gain insight in these areas, we investigate catalytic mechanisms of CH4 and CO2 decomposition and adsorption on graphene. Ab initio molecular dynamics is employed to simulate the reactions. It is based on density functional theory and allows us to determine accurate quantum-mechanical forces acting on atoms. Free energy profiles are calculated from so-called Blue Moon ensemble simulations with controlled temperature either close to the standard state (300 K) or at typical CVD growth temperature (1200 K). Calculated energy barriers on graphene are significantly lower than experimental bond dissociation energies for isolated molecular gases. This shows that graphene acts as a catalyst for methane decomposition. Calculations show different preferred mechanisms of CO2 adsorption, depending on surface morphology. On ideal graphene, dissociative adsorption is preferred whereas on defect sites, such as the Stone-Wales defect, direct chemisorption of CO2 occurs with higher likelihood.

V.4.4
17:00
Authors : Keisuke Natsui (1), Hitomi Iwakawa (1), Norihito Ikemiya (1), Kazuya Nakata (2), Yasuaki Einaga (1) (3)
Affiliations : (1) Department of Chemistry, Keio University, Japan; (2) Photocatalysis International Reseach Center, Tokyo University of Science, Japan; (3) JST-ACCEL, Japan

Resume : In recent years, the electrochemical reduction of carbon dioxide to useful chemicals and fuels has attracted much attention. Formic acid is one of the important products obtained by the electrochemical reduction of carbon dioxide, because it can be used as fine chemical and as a fuel for direct fuel cell (X. Lu, et al. ChemElectroChem, 2014, 1, 836.). Formic acid has been obtained with high faradaic efficiency using Sn, Hg, and Pb electrodes which have high hydrogen overpotential (Y. Hori, et al. Electrochim. Acta, 1994, 39, 1833.), but these electrodes have high toxicity. Therefore, we focus on boron-doped diamond (BDD) electrode which is composed only of carbon and boron and has wide potential window in an aqueous solution. Herein, we investigated the electrochemical reduction of carbon dioxide on BDD electrode to produce formic acid with high faradaic efficiency. In order to achieve the highly efficient production of formic acid, we used a circulation flow reactor. Formic acid was obtained as the main product with the faradaic efficiency of more than 90% by the electrochemical reduction in 0.5 M KCl aqueous solution saturated with carbon dioxide at ?2 mA/cm2 for 1 hour with a flow rate of 100 mL/min using the circulation flow reactor, though the faradaic efficiency was at most 49% using a batch reactor. Furthermore, the faradaic efficiency for the production of formic acid increased up to 95% with increasing the flow rate.

V.4.5
17:15
Authors : Xie Quan*, Yanming Liu
Affiliations : Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China

Resume : Electrochemical reduction of CO2 is an attractive strategy for global warming mitigation and converting it into useful chemicals. However, it suffers from low efficiency and poor product selectivity, especially for producing fuels with multicarbon or high heating value. Here, N-doped or B/N-codoped nanodiamond (denoted as NDD and BND) were reported as efficient and stable electrodes for selective reduction of CO2 to acetate or ethanol. NDD electrode preferentially and rapidly converted CO2 to acetate over formate with a low overpotential of 0.12 V, overcoming the usual limitation of low selectivity for C2 products. The faradic efficiency for CO2 reduction was 91.8% at ?1.0 V (vs RHE). Its superior performance for CO2 reduction could be attributed to its high overpotential for hydrogen evolution and N doping, where N-sp3C species was highly active for CO2 reduction. The possible pathway for CO2 reduction on NDD was CO2 ? CO2?? ? (COO)2? ? CH3COOH. Interestingly, when nanodiamond was codoped by B and N, it selectively reduced CO2 to ethanol with high current efficiency of 93.2%, which overcame the limitation of low selectivity for multicarbon or high heating value fuels. Experiments combined with density function theory (DFT) calculation revealed the synergistic effect of B and N codoping is crucial for high ethanol selectivity, and the pathway for CO2 reduction on BND was *CO2 ? *COOH ? *CO ? *COCO ? *COCH2OH ? *CH2OCH2OH ? CH3CH2OH.

V.4.6
 
Poster Session I : Oliver Williams, Xiaodong Zhuang, Teruhiko Matsubara
17:30
Authors : Otieno Kevin Okoth, Kai Yan, Jingdong Zhang*
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, P.R. China

Resume : Mo-BiVO4 and graphene nanocomposites were prepared and explored as photoactive material to construct a visible light-driven photoelectrochemical biosensor. The photoelectrochemical measurements indicated that suitable amount of graphene incorporated into Mo-BiVO4 greatly promoted the photocurrent response, owing to improved charge transfer rate and enhanced absorption of visible light. Moreover, graphene in the nanocomposites played a crucial role in immobilization of streptomycin aptamer through π-π stacking interaction. In the absence of streptomycin, photoelectrochemical aptasensor exhibited a weak photoresponse due to steric hindrance from the aptamer. After specific interaction between streptomycin and the aptamer, the sensor exhibited an enhanced photocurrent response to streptomycin, attributed to the oxidation of streptomycin molecules by photogenerated holes. Under optimal conditions, the designed photoelectrochemical sensor exhibited a linear photocurrent response to streptomycin in the concentration range of 0.1 to 100 nM, with a detection limit (3S/N) of 0.0481 nM. The applicability of the PEC aptasensor was successfully assessed by measuring streptomycin in commercial veterinary drugs.

V.P1.1
17:30
Authors : Romário Araújo Pinheiro, Amanda Araújo Silva, André Contin, Vladimir Jesus Trava-Airoldi, Evaldo José Corat
Affiliations : National Institute for Space Research, São José dos Campos, 1758, Astronautas Avenue, 12227-010, Brazil.

Resume : Vertically Aligned Carbon Nanotubes (VACNTs) are known by their superhydrophobic and superhydrophilic behaviors. In addition, microfluidic devices fabricated with them are successful employed to fluids control inside micro channels. When modified this material presents potential properties for water collecting from fog or humidify atmosphere. In this work, we studied the modification of VACNTs surface by the well known CO2 laser irradiation technique. We aim to obtain a selective oxidation of VACNTs only by CO2 laser irradiation. The catalyst metallic particles were deposited on stainless steel by spin-coating method. VACNTs growth was carried out by thermal CVD method in a tubular reactor at 700°C. An argon flow dragged the camphor vapor into the active zone. The CO2 laser was used in first step to irradiate samples in N2 atmosphere. This step was performed at high laser power to obtain stable superhydrophobic structure and to remove amorphous carbons remained after the CVD process. These stable structures consist of carbon nanotubes tips joined by laser heating. In next step, the samples were irradiated by laser at low power in air for carbon nanotubes oxidation. Morphologic and structural analyses were performed by Raman Spectroscopy, Scanning Electron Microscopy with Field Emission Gun (SEM-FEG) and X-Ray Diffraction. The samples wettability was verified by contact angle (CA) analyses. Electrochemistry analyses were performed to study modified VACNTs electrochemical behavior. The Fourier Transform Infra-Red (FTIR) was performed for identify the functional groups on CNTs surface. The Raman spectra and X-Ray diffractogram showed that after laser heating there is an increase in CNTs structural defects amount. VACNTs superhydrophilicity was observed through the CA measurements.

V.P1.2
17:30
Authors : Amanda Araújo Silva, Romário Araújo Pinheiro, Vladimir Jesus Trava-Airoldi, Evaldo José Corat
Affiliations : National Institute for Space Research, São José dos Campos, Brazil

Resume : Multi-Walled Carbon Nanotubes (MWCNTs), often described as rolled graphene sheets, could be an alternative to graphene obtainment or to produce a nanocomposite based on carbon nanotubes and graphene. A nanocomposite is an interesting alternative to improve CNTs properties, such as surface area and capacitive behavior. Plasma treatments and chemical oxidation are well-known techniques that enable graphene extraction by the carbon nanotubes exfoliation. In this study we have demonstrated an effective process to obtain MWCNTs/graphene sheets nanocomposite by Hot Filament Chemical Vapor Deposition (HFCVD) technique at low vacuum. The exfoliation process is based on the collision of hydrogen ions on the carbon nanotubes walls surface. The MWCNTs were synthesized by thermal chemical vapor deposition at 700°C. Fe-Co solution was used as catalyst particles source. For exfoliation process, we used a HFCVD reactor at 50 Torr and 100 sccm H2 flow. The samples were characterized by Raman Scattering Spectroscopy, Scanning Electron Microscopy with Field Emission Gun (SEM-FEG), X-Ray Diffraction (XRD) analysis, Fourier Transform Infrared (FTIR) and electrochemical analyses. MWCNTs exfoliation was observed in SEM micrographs, in which carbon nanotubes presented open edges on their surfaces. In Raman spectra, we notice an increase in defects density after exfoliation process by the raise in D band intensity. XRD patterns showed a decrease in (002) peak intensity and the emergence of a peak at around 10°, corresponding to (001) planes diffraction. The nanocomposite presented high capacitance value compared to MWCNTs electrodes. Further, HFCVD showed itself to be a promising alternative for MWCNTs/graphene sheets nanocomposite obtainment.

V.P1.3
17:30
Authors : Jing Zou, Ming Lei (co-first), Yanjuan Sun, Sheng Zhang,Yi Liu, Shengli Wu, Yuan Cao, Jizhou Jiang
Affiliations : Key Laboratory for Green Chemical Process of Ministry of Education, School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430205, China; Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education, Hubei Province, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074, China; Department of Physics, National University of Singapore, 2 Science Drive 3, 117542,Singapore.

Resume : A typical 2D/2D CuS/g-C3N4 nanocomposites were prepared by a simple microwave-assisted method. The as-prepared CuS nanosheets showed regularly hexagonal with an average thickness of 10 nm, which loaded on the surface of g-C3N4 with single or few layers. It was found that 2D/2D CuS/ g-C3N4 nanocomposites exhibited a distinctly enhanced visible light- Fenton like catalytic performance toward degradation of Rhodamine B (RhB) in water as compared to blank CuS nanosheets and g-C3N4, as well as the similar CuS/g-C3N4 nanocomposites with 1D/2D or 3D/2D structures. ESR measurements and radicals captured experiments indicated that hydroxyl radical (•OH) was the main active species in the system. The enhanced activity was attributed to the intimate interfacial contact and unique 2D/2D morphology associated with CuS nanosheets and g-C3N4 nanosheets, which were beneficial for the transfer and separation of photogenerated charge carriers over CuS/g-C3N4 nanocomposites upon visible light irradiation, and thereby expediting the activation of H2O2 to form •OH and the circulation of Cu(Ⅰ)/Cu(Ⅱ). In addition, the visible light-Fenton like catalytic performance of as-prepared 2D/2D g-C3N4/CuS nanocomposites were influenced by g-C3N4 content, catalysts load and solution pH value. Under the optimal conditions with an irradiation of visible light, the 2D/2D nanocomposites yielded rapid completed degradation of Rhodamine B with an apparent rate constant of 0.38 min-1.

V.P1.4
17:30
Authors : Xiaolan Penga,b, Wen Yuana,b, Jiaxiu Zoua,b, Bing Wangb,*, Wenyuan Hub, and Ying Xionga,*
Affiliations : a State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science & Technology, Mianyang 621010, P. R. China b School of Materials Science & Engineering, Southwest University of Science & Technology, Mianyang 621010, P. R. China

Resume : Novel nitrogen-incorporated ultrananocrystalline diamond/multilayer graphene (N-UNCD/MLG) composite carbon films were deposited on silicon substrates via a microwave plasma chemical vapor deposition (MPCVD) method, in which diethylamine was utilized as the sole carbon and nitrogen sources. In the composite films, MLGs are grown vertically on substrate surface and interlaced together to build a porous nest-like morphology. Many ultra-small N-UNCDs are dispersed uniformly inside the ?nest?. Using [Fe(CN)6]3-/4- as redox probe, the electrochemical activity of N-UNCD/MLG films is investigated. It exhibits a fast electron transfer kinetic behavior and large electrochemical active surface area. The N-UNCD/MLG films process large electrochemical double layer capacitance (EDLC) of 327.4 ?F?cm-2 for cyclic voltammetry (CV) measurement and of 306.5 ?F?cm-2 for glavanostatic charge-discharge (GCD) measurement. After 10000 charge/discharge cycles, the reduction of EDLC is only about 10.3%. For the application of electrochemical sensors, this film presents low detection limits: ~ 3.8 ppb for Ag+ and ~ 0.41 ?M toward dopamine. Therefore, the N-UNCD/MLG films with high electrochemical activity and large EDLC as well as robust cyclic stability would be a new class of carbon-based electrode for the application in electrochemical energy storage and electrochemical sensing.

V.P1.5
17:30
Authors : Rei Nonomura1, Takashi Itoh2, Yoshinori Sato3, Masashi Yamamoto3, Tetsuo Nishida3, Kazuyuki Tohji1, Yoshinori Sato1,4
Affiliations : 1Graduate School of Environmental Studies, Tohoku University, Japan, 2Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Japan, 3Stella Chemifa Co., Japan, 4Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Japan

Resume : Vertically aligned carbon nanotubes (VACNTs) have been utilized as electrodes of electric double-layer supercapacitors (EDLSCs) because of their excellent electrical properties by which the EDLSCs exhibit high power densities with keeping specific capacitances, in compared with activated carbon electrodes. In chemically functionalized CNTs, the specific capacitances are larger than those of unfunctionalized CNTs. Therefore, functionalized VACNTs are great candidates as electrodes for high-performance EDLSCs. Here we report the synthesis of nitrogen-doped vertically aligned multi-walled carbon nanotubes (VAMWCNTs) via defluorination[1,2] and their electrochemical properties. As-grown VAMWCNTs synthesized by a chemical vapor deposition method were fluorinated using a gas mixture of 20% F2/N2 at 250 °C for 30 min. The fluorinated-VAMWCNTs (F-VAMWCNTs) were reacted with ammonia in a flow of a mixture of 1% NH3/N2 gas at the temperature of 573-873 K for 30 min (N-VAMWCNTs). The samples were characterized using scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and Raman scattering spectroscopy. Electrochemical properties were evaluated by cyclic voltammetry and AC impedance spectroscopy using a two or three electrode coin-type cell in propylene carbonate (PC) electrolyte containing trietylmethylammonium tetrafluoroborate (TEMABF4)[3]. We will report the detailed data in this presentation. [1] K. Yokoyama et al. Carbon 94, 1052 (2015). [2] K. Yokoyama et al. J. Mater. Chem. A 4, 9184 (2016). [3] Y. Honda et al. J. Power Sources 185, 1580 (2008).

V.P1.7
17:30
Authors : Hui Lia, Qijin Wana*, Yuanyuan Zhanga, Nianjun Yanga,b*
Affiliations : [* Corresponding author. E-mail address: qijinwan@wit.edu.cn (Qijin Wan), nianjun.yang@uni-siegen.de (Nianjun Yang).] a School of Chemistry and Environmental Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430073, China b Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Large electrode area and highly active catalyst play key roles in the electrocatalytic oxidation of liquid fuels such as alcohols, carboxylic acids, aldehydes and methanol. In this paper, expanded graphite-carbon nanotubes (EG-CNTs) composite with different mass ratios were employed as the catalyst support. Expanded graphite (EG) was prepared through microwave treatment. Expanded graphite-carbon nanotubes (EG-CNTs) composite was synthesized using ultrasonic method. The mass ratios of expanded graphite and carbon nanotubes were varied during synthesis. The electrocatalysts of palladium nanoparticles (Pd NPs) were electrodeposited. Pd NPs/EG-CNTs nanocomposites were characterized using scanning electron microscopes (SEM), transmission electron microscope (TEM), X-ray photoelectron spectrometry, Brunauer-Emmett-Teller measurements, and electrochemical techniques. Electrochemical activity and double-layer capacitance of EG-CNTs, EG and CNTs were studied. Electrocatalytic oxidations of alcohols, carboxylic acids, aldehydes and methanol were investigated on Pd NPs/EG-CNTs nanocomposite coated electrode in alkaline medium. The oxidation peaks of those liquid fuels observed at the forward direction: the forward scan (positive-potential) and reverse scan (negative-potential), are associated to the incompletely oxidized carbonaceous species. Such a Pd NPs/EG-CNTs nanocomposite coated electrode is promising to be applied as the anode for the facilitation of direct fuel cells.

V.P1.8
17:30
Authors : Peng Yan a, Qijin Wan a*, Yuanyuan Zhang a, Nianjun Yang a,b*
Affiliations : [* Corresponding author. E-mail address: qijinwan@wit.edu.cn (Qijin Wan), nianjun.yang@uni-siegen.de (Nianjun Yang).] a School of Chemistry and Environmental Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430073, China; b Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Chromium-based metal-organic framework (MOF) MIL-101(Cr) was prepared via a hydrothermal method, followed by the hybridization with reduced graphene oxide (rGO) through dispersing pre-synthesized MOF powder in the well-dispersed GO suspensions and a reduce treatment using hydrazine hydrate. The morphology and structure of as-prepared MIL-101(Cr)@rGO composite were characterized using scanning electron microscope, transmission electron microscope, Raman spectroscopy, and Brunner-Emmett-Teller measurements. Meanwhile, the electrochemical performance of the composite was checked with cyclic voltammetry and electrochemical impedance spectroscopy. Due to the synergistic effect from high conductivity of rGO and large specific surface area of MIL-101(Cr), the electrochemical signals of 4-nonylphenol (4-NP) were significantly improved on MIL-101(Cr)@rGO modified electrode, and a sensitive electrochemical sensor for 4-NP was successfully fabricated. By applying differential pulse voltammetry, the sensitive and rapid monitoring of 4-NP was realized in the range of 0.1 to 12.5 μM. The detection limit was as low as 10 nM. Such an electrochemical sensor is thus promising for the environmental monitoring of 4-NP in future.

V.P1.9
17:30
Authors : Jun Yu a, Qijin Wan a*, Yuanyuan Zhang a, Nianjun Yang a,b*
Affiliations : [* Corresponding author. E-mail address: qijinwan@wit.edu.cn (Qijin Wan), nianjun.yang@uni-siegen.de (Nianjun Yang).] a School of Chemistry and Environmental Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430073, China b Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Carbon materials with different carbon-carbon covalent bonding and arrangement of the carbon atoms have different properties and eventually lead to various applications. In this work, electrochemical properties of several sp2 hybridized carbon materials, such as graphene nano platelets (GNPs), carbon nanotubes (CNTs), graphene oxide (GO), aminited graphene (NH2-Gr), expanded graphite (EG), and their composite materials including EG-GNPs, EG-CNTs, EG-GO, EG-NH2-Gr, have been studied. These properties include electrochemical activity of redox probes as well as their electrical double layer capacitances. For example, the voltammetric behavior of negatively charged redox probes (Fe(CN)63-/4-) on composite materials with different mass ratios revealed that EG-based composite carbon material (w/w = 2:1) owns a larger effective area and a lower background current. Electrochemical sensing of positively, negatively and neutrally charged inorganic ions, including Pb2+, NO2-, sunset yellow and tartrazine, were conducted as well on EG, EG-CNTs and EG-GNPs, respectively. EG-based composite carbon materials have shown the highest electrochemical activity and it will be the most promising electrode material for electrochemical sensing of these electrolytes.

V.P1.10
17:30
Authors : Yuanyuan Zhang a, Qijin Wan a*, Nianjun Yang a,b*
Affiliations : [* Corresponding author. E-mail address: qijinwan@wit.edu.cn (Qijin Wan), nianjun.yang@uni-siegen.de (Nianjun Yang).] a School of Chemistry and Environmental Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Lab of Novel Reactor & Green Chemical Technology, Wuhan Institute of Technology, Wuhan 430073, China; b Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Cu(II), Pb(II) and tetrabromobisphenol A (TBBPA) are three kinds of widely existing e-waste persistent pollutants. Since their electrochemical signals are distributed from negative potential region to positive one, there are relatively few reports dealing with simultaneous and electrochemical detection of Cu(II), Pb(II) and TBBPA up to now. Herein, porous graphene was laoded with nano-CeO2 via hydrothermal reaction. Such an composite was expected to feature an improved catalytic activity from nano-CeO2 and eventually construct a highly sensitive electrochemical sensor for the simultaneous detection of Cu(II), Pb(II) and TBBPA. The influence of the morphology (more exactly shape-effect) and exposed crystal facets of nano-CeO2 on the electrochemical sensing of Cu(II), Pb(II) and TBBPA was investigated. On these nanocomposites, their oxidation peak currents were much enhanced. This results from a synergistic effect from high catalytic activity of the specifically shaped CeO2 nanocrystal and good conductivity/high surface area of porous graphene. Finally, novel electrochemical interfaces were developed for highly sensitive, selective and simultaneous detection of Cu (II), Pb (II), and TBBPA. These methods based electrochemical sensors are promising for the in-situ and rapid analysis of trace amount of e-waste persistent pollutants in different environments.

V.P1.11
17:30
Authors : Bao-Ping Qi, Shenghui Zhang
Affiliations : Hubei Key Laboratory of Biologic Resources Protection and Utilization, College of Chemistry and Environmental Engineering, Hubei University for Nationalities, Enshi 445000, China

Resume : Except the tunable photoluminescent property, graphene quantum dots (GQDs) with special structures have also exhibited other novel properties. Herein, GQDs played a novel coreactant role in Ru(bpy)(3)(2 )/GQDs system to increase the anodic ECL signal of Ru(bpy)(3)(2 ), which has been testified by ultraviolet, fluorescence, and electrochemiluminescence (ECL) experiments. Based on the coreactant mechanism of Ru(bpy)(3)(2 )/GQDs system, a chlorinated phenol-related quenching ECL sensor was designed and the sensor showed a good linear relationship in the range from 0.60 to 55 μM with the detection limit of 1.4 × 10-8 M (S/N = 3). These results were not only beneficial to resolve the structure of GQDs, but also expanded the application field of GQDs.

V.P1.12
17:30
Authors : Xiuxiu Han, Xili Tong*, Gangpin Wu, Nianjun Yang, Xiang-Yun Guo
Affiliations : State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, PR China;University of Chinese Academy of Sciences, Beijing 100049, PR China;Institute of Materials Engineering, University of Siegen, Siegen 57076, Germany

Resume : The development of efficient and earth-abundant electrocatalysts on carbon substrates for oxygen evolution reaction (OER) is of great significance since they are widely employed in the flexible power sources, such as for fuel cells, metal-air batteries, and water splitting. Carbon materials are often applied as the catalyst support, while metal/metal oxides are used as the catalysts. Here, we introduce NiSe nanowire arrayswas grown on nickel coated carbon fibers (CFs) as a novel electrocatalysts for OER. They were electrochemically synthesized by a simple hydrothermal process. Benefiting from their structural merits of such a nanocomposite (NiSe-Ni/CF) and the in-situ formed catalytically active species, the optimized NiSe-Ni/CF catalyst exhibits an excellent activity for OER. Anoverpotential of 283 mV was achieved at 10 mA cm-2 and a Tafel slope of 53 mV dec-1 in 1.0 M KOH. Its performance is superior to the commercial IrO2 catalysts. More importantly, the NiSe-Ni/CF catalyst shows no evidence of degradation after more than 120 h of continuous operation.

V.P1.13
17:30
Authors : Wei Wang1, Ting Bao1, Xi Zeng, Huayu Xiong, Wei Wen, Xiuhua Zhang, Shengfu Wang*
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China

Resume : In this work, a novel and ultrasensitive electrochemical biosensor was constructed for DNA detection based on functionalized gold clusters/graphene nanohybrids (AuNCs/GR nanobybrids) and exonuclease III (Exo III)-aided cascade target recycling. By utilizing the capacity of GR as universal template, different metal nanoclusters including AuNCs/GR nanobybrids and PtNCs/GR nanohybrids were synthesized through convenient ultrasonic method. Exo III-aided cascade recycling was initiated by target DNA, generating the final cleavage product (S2), which acted as a linkage between capture probe and the functionalized metal nanoclusters/GR conjugates in the construction of the biosensor. The AuNCs/GR-DNA-enzyme conjugates acted as interfaces of enzyme-catalyzed silver deposition reaction, achieving DNA detection ranging from 0.02 fM to 20 pM with a detection limit of 0.057 fM. In addition, PtNCs/GR-DNA conjugates presented peroxidase-like activity and the functionalized PtNCs/GR nanohybrids-based electrochemical biosensor also realized DNA detection by catalyzing the 3,3?,5,5?-tetramethylbenzidine-hydrogen peroxide (TMB-H2O2) system to produce electrochemical signal. This metal clusters/GR-based multiple-amplified electrochemical biosensor provided an universal method for DNA detection.

V.P1.14
17:30
Authors : Yijia Wang, Xiaoning Bai, Wei Wen, Xiuhua Zhang, Shengfu Wang*
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China

Resume : Since Human Immunodeficiency Virus (HIV) have been one of the most terrible virus in recent decades, the early diagnoses of HIV gene is of great importance for all the scientist around the world. In our work, we developed a novel electrochemical biosensor based on one step ultrasonic synthesized graphene stabilized gold nanoclusters (GR/AuNCs) modified glassy carbon electrode (GCE) with exonuclease III (Exo III)- assisted target recycling amplification strategy for the detection of HIV DNA. It?s the first time that GR/AuNCs was used as biosensor platform and aptamer with Cytosine-rich base was set as capture probe to construct biosensor. With the combination of Cytosinerich capture probe, GR/AuNCs ?s good conductivity and high surfaces with Exo IIIassisted target recycling amplification, we realized high sensitivity and good selectivity detection of target HIV DNA with a detection limit of 30 aM (S/N=3). Furthermore, the proposed biosensor has a promising potential application for target detection in human serum analysis.

V.P1.15
17:30
Authors : Tianxing Hu, Le Zhang, Wei Wen*, Xiuhua Zhang, Shengfu Wang*
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China.

Resume : A specific and sensitive method was developed for quantitative detection of miRNA by integrating horseradish peroxidase (HRP)-assisted catalytic reaction with a simple electrochemical RNA biosensor. The electrochemical biosensor was constructed by a double-stranded DNA structure. The structure was formed by the hybridization of thiol-tethered oligodeoxynucleotide probes (capture DNA), assembled on the gold electrode surface, with target DNA and aminated indicator probe (NH2-DNA). After the construction of the double-stranded DNA structure, the activated carboxyl groups of graphene quantum dots (GQDs) assembled on NH2-DNA. GQDs were used as a new platform for HRP immobilization through noncovalent assembly. HRP modified biosensor can effectively catalyze the hydrogen peroxide (H2O2)-mediated oxidation of 3,3?,5,5?-tetramethylbenzidine (TMB), accompanied by a change from colorless to blue in solution color and an increased electrochemical current signal. Due to GQDs and enzyme catalysis, the proposed biosensor could sensitively detect miRNA-155 from 1 fM to 100 pM with a detection limit of 0.14 fM. High performance of the biosensor is attributed to the large surface-to-volume ratio, excellent compatibility of GQDs. For these advantages, the proposed method holds great potential for analysis of other interesting tumour makers.

V.P1.16
17:30
Authors : Wei Xu, Huayu Xiong, Wei Wen, Xiuhua Zhang*, Shengfu Wang
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China

Resume : Carbon nanotubes (CNTs) have received significant interest because of their dimensions and structure-sensitive properties since CNTs were discovered by Iijima in 1991. CNTs show electrical properties as metal or semiconductors, depending on their size and lattice helicity. The subtle electronic properties suggest that CNTs, when used as an electrode material in electrochemical reactions, have the ability to promote electron-transfer reactions. Incorporation of CNTs into polymers can lead to new composite materials possessing the properties of each component with a synergistic effect that would be useful in particular applications, which lead nanotubes became the ideal additives for structural and functional composites. Molecularly imprinted polymers (MIPs) have a lot of advantages, such as excellent specific recognition function, unique physical, chemical and mechanical features, resistance to severe environment, long service life?good stability, and can be recycled, and so on. For this reason, MIPs could be widely used in the separation, detection and molecular catalysis and other fields. In this work, the CNT-MIPs sensors were developed by sol-gel polymerization with single-wall carbon nanotubes via taking agonists as template molecule, respectively. The imprinted sensors showed high recognition ability and affinity, and were successfully applied to the determination of agonists in real samples.

V.P1.17
17:30
Authors : Jing-Yi Huang, Ting Bao, Tian-Xing Hu,Wei Wen*, Xiu-Hua Zhang, Sheng-Fu Wang
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University, Wuhan 430062, China.

Resume : A strategy was developed for the voltammetric determination of the antibiotic drug levofloxacin (LV) based on a glassy carbon electrode modified with a composite consisting of poly(o-aminophenol) and graphene quantum dots (PoAP/GQD) that was fabricated by electropolymerization. The PoAP/GQD composite provides a large surface area and sensing interface and strongly promotes the oxidation current of LV. Under optimal conditions, the modified GCE displays an oxidation peak current (best measured at a working voltage of 1.05 V vs. SCE) that is linearly related to the levofloxacin concentration in the range from 0.05 to 100 ?M, and the detection limit is 10 nM (at an S/N of 3). The method was applied to the determination of levofloxacin in spiked milk samples where is gave recoveries between 96.0 and 101.0 %.

V.P1.18
17:30
Authors : Bingjie Hou, Huaizhi Liu, Shaopeng Qi, Yinyan Zhu, Xiaoqing Jiang*, Lihua Zhu*
Affiliations : Jiangsu Key Laboratory of New Power Batteries, College of Chemistry and Materials Science, Nanjing Normal University, 1 Wenyuan Road, Nanjing 210023, PR China; Department of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China

Resume : High quality pristine graphene (PG) dispersions are prepared conveniently via an organic salts assisted exfoliation method in a green, non­toxic, cheap and low boiling point solvent: ethanol. The PG is characterized by transmission electron microscopy and atomic force microscopy. Furthermore, the PG is used as an electrode material for fabrication nonenzymatic sensor of hydrogen peroxide (H2O2). This nonenzymatic sensor shows enhanced electrocatalytic activity towards H2O2 and displays two linear ranges from 2.0 to 37 µM and 37 to 437 µM with a detection limit of 0.19 µM (S/N = 3), which is comparable to those electrochemical sensors based on metal oxide or noble metal/graphene composites.

V.P1.19
17:30
Authors : Siyu Yu, Michael Vogel, Nianjun Yang, Soumen Mandal, Oliver A. Williams and Xin Jiang
Affiliations : Siyu Yu, Michael Vogel, Nianjun Yang and Xin Jiang: Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany; Soumen Mandal and Oliver A. Williams: School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA, UK.

Resume : Boron doped diamond (BDD) has been utilized as an electrode material and the electrode supporter for the construction of electrochemical capacitors (ECs), due to its wide electrochemical potential window in different solutions and long lifetime under various harsh conditions as well as the possibility of enlarging its surface area. For example, various nanostructures (e.g. diamond paper, diamond network, etc.) have been utilized successfully for the construction of ECs, including electrical double layer capacitors (EDLCs) with inert electrolytes and pseudocapacitors with redox electrolytes. On the other hand, as the electrode supporter, BDD has been coated with metal oxides (e.g., MnO2, NiOx) to construct pseudocapacitors. However, the poor stability of metal oxides on BDD surface limited the performance of these pseudocapacitors. To construct capacitor electrodes, especially those which have large surface areas and can remain their own long stability as well as the stability of pseudo-active species on their surfaces, is therefore of great significance. In this presentation, a novel concept to construct diamond based ECs will be shown, where BDD will be used as the electrode supporter and vertical aligned carbon fibers as the capacitor electrode. The growth of vertical aligned carbon nanofibers on BDD was conducting with a thermal chemical vapor deposition reactor at 250 degrees. The sputtered copper thin films were applied as the catalyst and C2H2 as the reaction gas. The morphology, chemical structure, wettability, and conductivity of these vertically aligned carbon fibers were investigated using SEM, TEM, XPS, Raman, Contact angel and four-probe measurements, etc. They were further employed as the electrode to develop ECs, covering EDLCs and pseudocapacitors. The performances of these capacitors were investigated in the inert electrolyte (1.0 M H2SO4 solution) as well as in the redox electrolyte (0.05 M Fe(CN)63-/4-). For instance, in a two-electrode system, the capacitance reaches the value of 30 and 48 mF cm-2 at 10 mV s-1 in 1.0 M H2SO4 solution and 1.0 M Na2SO4 + 0.05 M Fe(CN)63-/4-, respectively. The related energy and power densities of these EDLCs are 22.9 Wh kg-1 and 27 kW kg-1, respectively. While for these pseudocapacitors, they are 44 Wh kg-1 and 25 kW kg-1, respectively. For both ECs, the capacitances keep unchanged even after 10000 cycles at a current density of 5 mA cm-2. The performance of these vertically aligned carbon fibers based ECs will further compared with other carbon based ECs published in the literature.

V.P1.20
17:30
Authors : Mei Liu, Wei Xiong, Shantang Liu
Affiliations : School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, 693 Xiongchu Road Wuhan 430073, China

Resume : Here we demonstrate an oil-in-water emulsions process via a one-pot method to fabricate nitrogen-doped hierarchically porous carbon foams (N-HPCFs). There is a stabilized hydrogen-bonding interaction between carbon precursor resorcinol/ formaldehyde (R/F) resol and nitrogen precursor melamine in the presence of cosurfactant ethylene glycol (EG). Structural characterization indicate that the as-prepared N-HPCFs are hierarchically porous with high specific surface area (SSA) up to 1525 m2g−1 and high pore volume (0.83 cm3g-1) without KOH activating. The macropores come from the pyrolysis of EG and oil phase, the mesopores are ascribed to the soft template Pluronic F127. With the introduction of potassium citrate, rich nano-sized pore structures and high porosity are promoted. As electrodes for supercapacitors, N-HPCFs exhibit a high specific capacitance up to 328 F/g at 1A/g in a three-electrode system using 6 M KOH electrolyte, and good stability with over 93% capacitance retention after 5000 cycles at 10 A/g. Therefore, such a N-doped hierarchical carbon foam is a promising high-performance electrode for energy storage devices. Keywords: Nitrogen-doped, Emulsions, Hierarchically, Porous carbon foam, Supercapacitors

V.P1.21
17:30
Authors : Tian Gan*, Zhikai Wang, Zhaoxia Shi
Affiliations : College of Chemistry and Chemical Engineering; Xinyang Normal University; Xinyang 464000; China

Resume : In recent years, considerable effort has been devoted to fabrication of core-shell structure nanomaterials with tunable functional properties. Amongst them, the noble metal@inorganic oxide ones have become a subject of intense interest in various fields due to their outstanding properties. Furthermore, various approaches have also been developed to increase the electronic conductivity and hydrophilicity of the noble metal@inorganic oxide type core-shell nanoparticles, such as carbon coating or adding conductive additive. Especially, graphene oxide (GO), the derivative of graphene, has large specific surface area, good suspension stability and a large number of edge sites, which can produce many electrochemically active sites for electron transfer during voltammetric measurements. However, little attention has been devoted to the synthesis of core-shell structure nanocomposites with controllable core morphologies and the preparation of Ag/Cu2O/GO composites. Herein, we reported a method to synthesize GO enlaced and wrapped core-shell structured Ag@Cu2O with controllable morphology. Cu2O nanoshell anchored on the surface of Ag nanosprim in the diameter of 70-140 nm to prevent Ag from aggregating and pulverization. In addition, core-shell Ag@Cu2O was encapsulated by conductive networked GO, which acted as a percolated film entwining the Ag@Cu2O nanosprim to construct a 3D conductive network, facilitating the massive electron and analytes transport at fast rate. The Ag@Cu2O@GO modified electrode showed sensitive current response towards the simultaneous oxidation of dopamine (DA), uric acid (UA), guanine (G) and adenine (A), with wide linear response ranges and low detection limits.

V.P1.22
17:30
Authors : Koji Yokoyama1, Yoshinori Sato2, Masashi Yamamoto2, Tetsuo Nishida2, Kazuyuki Tohji1, Yoshinori Sato1,3
Affiliations : 1. Graduate School of Environmental Studies, Tohoku University; 2. Stella Chemifa Corporation; 3. Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University

Resume : Nitrogen-doped single-walled carbon nanotubes (N-SWCNTs) are fascinating materials as alternatives to high-cost platinum catalysts for oxygen reduction reaction (ORR) on the cathode of polymer electrolyte fuel cells. In N-SWCNTs, pyridinic- and graphitic-type nitrogen species (Py-N and Gr-N) have been regarded as the catalytic active sites for ORR. In order to improve their catalytic activities, it is essential to identify which nitrogen species serves as the active site. Here we report defluorination-assisted nitrogen doping to SWCNTs and further annealing effect to selectively synthesize Py-N or Gr-N enriched N-SWCNTs. N-SWCNTs were prepared heating fluorinated SWCNTs (F-SWCNTs) at 400 °C in NH3 flow. The N-SWCNTs contained 3.0 at% nitrogen and the Py-N was 80% of the total nitrogen species. Furthermore, when the N-SWCNTs were annealed at 1000 °C in N2 flow, the ratio of Gr-N to the total nitrogen species was 50%. Judged from the onset potential and number of electrons transferred per oxygen molecule in ORR, the annealed N-SWCNTs possessed higher ORR catalytic activity than that of the N-SWCNTs, suggesting that Gr-N serves as the active site. In addition, the ORR catalytic activity of annealed F-SWCNTs which were prepared heating the F-SWCNTs under the same annealing condition as a reference, was inferior to that of the annealed N-SWCNTs, indicating the doped nitrogen species are crucial factors on the ORR catalytic activity.

V.P1.23
17:30
Authors : Peng Sun, Kaikai Zhang, He Zhou, Jianyu Gong, Zhao Wang, Md. Suzaul Islama, Yanrong Zhang
Affiliations : P. Sun, Environmental Science Research Institute, Huazhong University of Science and Technology; School of Energy and Environment, Inner Mongolia University of Technology; K. Zhang; H. Zhou; J. Gong; Z Wang; Md. Suzaul Islama; Yanrong Zhang, Environmental Science Research Institute, Huazhong University of Science and Technology;

Resume : The effect of sunflower stalk-derived biochar on p-nitrophenol (PNP) degradation with a thermally activated persulfate (PS) system was investigated in this study. The investigation of biochar with different pyrolysis temperatures on the effect of PNP degradation in the PS system at 60 ºC showed that 85.85%, 83.83%, 54.90% of PNP was degraded in 3 hours in the presence of biochar pyrolyzed at 1000, 650 and 500 ºC, respectively, accompanying a decomposition of PS with 100%, 88.60%, 31.50%; while only 34.09% of PNP and 10.75% of PS were decomposed in the absence of biochar, which demonstrated that both PNP degradation and PS dissociation to generate sulfate radical (SO4??) could be greatly enhanced with the presence of biochar and the enhancement was relative to the pyrolysis temperature of biochar. Raman study suggested that the higher content of defective sites (edges and vacancies) exsited in biochar with the higher pyrolysis temperature, which could be effectively accelerated the PS decomposition to generate SO4??. The findings from elemental analysis (EA), Fourier transform infrared spectroscopy (FT-IR), x-ray photoelectron spectroscopy (XPS), x-ray diffraction technique (XRD) and electrochemical impedance spectroscopy (EIS) revealed that the condensation and turbostratic crystallization of carbon increased with the increase of pyrolysis temperature, suggested that intact sp2-conjugated ? system on biochar played an important role on the enhancement of PS dissociation to generate SO4?? and PNP degradation. This study showed that the excellent catalyst property of biochar to the PS activation and organic pollutant removal, which may provide a new and green strategy for biochar application in pollutant removal.

V.P1.25
17:30
Authors : Haiyu Li, Qing LV, Qing Zhang
Affiliations : Chinese Academy of Inspection and Quarantine

Resume : Carbon nanotubes (CNTs) have some attractive intrinsic characteristics, such as mechanical, electronic, chemical and thermal stability, high resistance, elasticity, high surface area and good electrical conductivity. All these properties make CNTs a special material to be used in electroanalysis, especially due to its excellent performance of enhancing the electrochemical reactivity, promoting the electron-transfer reactions and alleviating surface fouling. Disposable electrochemical sensor is a recent trend in the application of electroanalysis, which provides a low-cost way to avoid tedious refreshing procedures and provides a possibility for standardized mass-production with high reproducibility. However, disposable electrochemical sensors based on CNTs is rarely investigated and applied. Here, we report a convenient and cheap approach to fabricate a stacked gold nanoparticles (AuNPs) film modified with CNTs. Paper with suitable roughness was firstly coated with gold nanoparticles via a simple physical vapor deposition (PVD) technique and then modified with multi-walled carbon nanotubes with the aid of a piece of filter paper. The surfaces in their intermediated and final stage were characterized by atomic force microscope, scanning electron microscope and electrochemical techniques. The obtained composite film is flexible with a low surface resistance, which is suitable for developing disposable electrochemical sensors. In this work, bisphenol A (BPA) was chosen to be a target molecule since it is one of the highest volume chemicals in the world and widely used in the synthesis of polycarbonate, epoxy resins and unsaturated polyester resins. Scientific reports also have verified that BPA could be concentrated into the environment from waste or into the human bodies from end-use products such as food-storage or packaging materials, toys, bottles and cans. Thus, it is of great importance to determine the BPA in trace amounts. BPA electrochemical sensor was fabricated by attaching a piece of plastic adhesive tape which punched with a round hole (5 mm diameter) on CNTs-AuNPs composite film with 16 mm long and 8 mm wide. The determination of BPA was investigated by linear sweep voltammetry (LSV) and the results showed that CNTs exhibited significant enhancement effects to BPA oxidation. A wide linearity in the range from 0.8 to 8 ?M with a detection limit of 0.13 ?M (S/N=3) was obtained. The within-sensor (n = 6) and between-sensor (n = 8) reproducibilities are 3.2% and 5.7% for 2 ?M BPA, respectively. The disposable sensor remains 85% of its activity after 10 continuous assays, indicating that it can also be used for repeated assays. The proposed sensor showed good resistance against interferences including Na+, Mg2+, K+, Cl?, SO42?, NO3?, Cu2+, Fe3+, Zn2+, Cr3+, Ni2+, catechol, hydroquinone, pentachlorophenol, paranitroaniline, and paranitrophenol. The proposed method has been used to detect BPA in real samples including ABS plastic toys and PC drinking bottles with satisfying results. This disposable sensor is readily mass-produced and could serve as a competitive candidate for practical applications.

V.P1.26
17:30
Authors : Z. Vlčkova Zivcova1*, V. Mortet2;3, A. Taylor2, A. Zukal1, O. Frank1 and L. Kavan1
Affiliations : 1 J. Heyrovsky Institute of Physical Chemistry of the AS CR, v. v. i., Prague, Czech Republic 2 Institute of Physics of the AS CR, v. v. i., Prague, Czech Republic 3 Czech Technical University in Prague, Faculty of Biomedical Engineering, Kladno, Czech Republic

Resume : Porous electrically conductive diamond layers with controlled enlargement of electrode specific surface area have been produced by deposition of boron-doped diamond (BDD) films on a porous template composed of SiO2 fibres using a multi-step spin coating process. This process resulted in a linear increase in BDD roughness factor with the number of spin coated layers. Specific surface area is determined from cyclic voltammetry (CV) and from the BET method. The differences in determination of roughness factor using these two methods are discussed. CV measurements of porous BDD are performed in aqueous electrolyte solutions with different pH values. The highest electrochemical double-layer capacitance of ca. 2 mF·cm-2 referenced to the projected geometric surface area is obtained for the thickest (25 μm) porous BDD electrode prepared by a 6 step spin coating process measured in 0.5 M H2SO4 electrolyte solution. The corresponding roughness factor of 677 is calculated. The capacitance value of the same porous BDD electrode normalized to the BET surface area (roughness factor 44) is significantly lower, i.e. 45 μF·cm-2. The electrocatalytic activity of porous BDD electrodes is studied using hexaamineruthenium(III/II) redox couple. The electrochemical cycle stability is determined by galvanostatic charge/discharge in PBS electrolyte solution. The charge retention of the thickest porous BDD samples after removing non-diamond carbon impurities by oxidative treatment is ca. 77 % after 3000 cycles. Acknowledgement: This work was supported by the Czech National Foundation (contract No. 13-31783S), and by the J.E. Purkyně fellowship awarded to V. Mortet by AS CR, v. v. i.

V.P1.27
17:30
Authors : Yang Yang, Shanshan Xu, Fan Zhang, Panpan Qin, Gang Li, Yongbing Tang, Wenjun Zhang
Affiliations : Functional Thin Films Research Center, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China

Resume : Hierarchical ZnCo2O4 particles hosted by 3D graphene network were synthesized through a one-pot hydrothermal synthesis approach. The as-synthesized ZnCo2O4-graphene composites showed an outstanding overall electrochemical performance as an anode of lithium ion batteries with high specific capacity and excellent cycling stability, i.e., a reversible capacity of 1920 mAh g-1 at a current density of 1000 mA g-1 after 300 cycles. In particular, at an elevated current density of 4000 mA g-1, a high capability of 1100 mAh g-1 could still be achieved, and it dropped by only 34% to 730 mAh g-1 after 2000 cycles. The synergistic roles of the hierarchically nanostructured ZnCo2O4 and highly-conductive 3D graphene networks in improving the specific capacity, rate performance, and cycling stability were discussed.

V.P1.28
17:30
Authors : Wenshuai Hu, Xiaoyu Zhao*, Shue Qiu, Zuoliang Sha, Juankun Zhang*
Affiliations : Tianjin University of Science and Technology(for all authors)

Resume : Nowadays, graphene/reduced graphene oxide has attracted more concerns because of its superior mechanical strength, low density and high heat conductance. The various applications have been developed on its mechanical, electrical and chemical properties. The property of graphene with larger surface area and better conductivity makes molecular imprinting electro-polymerization monomer to produce polymeric membrane with more effective imprinted sites, greater adsorption capacity and adsorption efficiency. Graphene and its composites is suitable for modifying electrochemical biosensors. In the last few decades, various papers have been reported about chemical, optical, adsorption and electronic properties of nanostructured materials. Especially AuNPs are used frequently as electrode surface in the fabrication of sensors/biosensors. In addition, the nano-sized AuNPs can enhance the electrode conductivity, the rate of electron transfer and the analytical sensitivity. Therefore, nano-sized AuNPs and its composites is suitable for building electrochemical biosensors. Erythrosine(ERT,C20H6I4Na2O5), as a synthetic pigment, often used in fruit flavor drinks, cakes, candy, dispensing wine, carbonated drinks and other foods. Because of their bright colors, good dyeing force, the price is cheap, widely used in food processing. But studies have shown that almost all of the synthetic pigments cannot provide nutrients to the human body, some synthetic pigment even endanger human body health for its carcinogenicity. Erythrosine belongs to a synthetic pigment and is a kind of widely used in food industry of colorants, due to the dangers of excessive edible has the potential to human body health, the daily intake of erythrosine are restricted. In view of the widespread existence of ERT and its harmfulness, to establish an efficient, fast, accurate, simple and economical method to detect ERT is very necessary. Molecularly imprinted polymers shows selective recognition of specific molecules caused by the covalent or non covalent interactions between the template molecules and functional monomers. It possesses the ability to selectively identify target molecules, and have the advantages of anti-acid and alkali resistance, good atability, easy preparation and so on. In this paper, a high sensitivity and quantitative detection of ERT molecularly imprinted membrane sensor was successfully constructed based on the electro-polymerization technology and a sensitive imprinted electrochemical sensor based on gold nanoparticles(AuNPs) in 2-aminoethanethiol(2-AET) functionalized graphene oxide(GO) modified glassy carbon(GC) electrode was fabricated for fast and direct determination of erythrosine. The main content of this paper includes the following : (1)Preparation of AuNPs, 2-AETGO and AuNPs/2-AETGO electrode via chemical synthesis. Afterwards, cAuNPs/2-AETGO was dropped on the GC electrode and then the modified electrode was dried under infrared heat lamp (AuNPs/2-AETGO/GCE). (2) Electrochemical measurements were performed on Ivium compact stat electrochemical workstation. The working electrode was AuNPs/2-AETGO/GC electrode, the reference electrode was Ag/AgCl electrode and the auxiliary electrode was a platinum electrode. Based on molecular imprinting technology, molecularly imprinted polymer membranes were prepared on the surface of AuNPs/2-AETGO/GCE by using electro-polymerization with m-dihydroxybenzene (m-DB) and o-phenylenediamine (o-PD) as monomers as the functional monomer and ERT as the template molecule. The electropolymerization was performed by cyclic voltammetry (CV). The polymerization solution contained o-PD, m-DB, ERT and PBS. Similarly, the non-imprinted polymer (NIP) modified electrode was prepared in the same way without addition of the template ERT. Immersing the electrode prepared above into a mixture solvent of Sodium hydroxide to remove the template ERT. Then, the GCE was rinsed in ultrapure water and dried it in nitrogen environment. (3) After the membrane was soaked and eluted, the molecular imprinted membrane was treated with specific recognition of ERT. Using differential pulse stripping voltammetry (DPV) and its peak current difference can measure, analyze and optimize the parameters that affect the performance of the sensor. CV and Electrochemical Impedance Spectroscopy(EIS) were used to characterize the molecularly imprinted membrane. (4)The surface and the molecular structure of the modified electrode were characterized by Scanning Electron Microscope (SEM), transmission electron microscope (TEM), and Fourier Transform Infrared Spectrometer(FT-IR). The basic electrochemical properties of AuNPs/2-AETGO/GCE were studied by means of CV, Electrochemical Impedance Spectroscopy (EIS) and differential pulse stripping voltammetry (DPV). (5) In the context of the optimal experimental parameters, the concentration of ERT solution was calibrated by the technology of DPV and study on the performance of molecularly imprinted sensor (MIP/AuNPs/2-AETGO/GCE). In addition, the specificity, the practical ability and the stability of the manufactured imprinted sensor were evaluated. After deducting the background current, the linearity range and the detection limit were obtained as 3.75 x 10-8 to 1.50 x 10-4 M and 4.77 x 10-9 M. It meets the requirements of ERT trace analysis. The sensor specifically bound to ERT quickly without sample pretreatment. In addition, the stability and reproducibility of the prepared molecular imprinted electrode were investigated. The excellent long-term stability and reproducibility of the prepared ERT imprinted electrodes make them attractive in electrochemical sensors.

V.P1.29
17:30
Authors : Yongkang Ye, Jingqi Xie, Shudong He, Hanju Sun and Xiaodong Cao*
Affiliations : School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China *e-mail: xiaodongcao@hfut.edu.cn

Resume : In this work, a label-free eletrochemical DNA biosensor has been developed assembled based on thionine functionalized reduced graphene oxide (THi-rGO) and gold nanoparticles (AuNPs) were eletrodeposited on the surface of the THi-rGO modified glassy carbon electrode (GCE), which not only employed as a functional matrix for capture DNA immobilization but also promoted electronic transfer. The hybridization capacity of the biosensor was based on the voltammetric response current of thionine before and after DNA hybridization. Under the optimal conditions, the amperometric signals decreased linearly with the concentration of complementary DNA, which ranged from 1×10^-17 M to 1×10^-13 M with a detection limit of 3.34×10^-18 M. The DNA biosensor showed the advantage of acceptable selectivity, stability and reproducibility.

V.P1.30
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Sensing : Tok Alfred
09:00
Authors : B. ZRIBI; D. KAMOUNI BELGHITI; P. BERGONZO and E. SCORSONE
Affiliations : CEA LIST, Diamond Sensors Laboratory

Resume : Conductive Boron Doped Diamond (BDD) is known as an outstanding electrode material exhibiting a wide electrochemical potential window in aqueous electrolytes (>3V), high chemical stability in harsh environments and/or at high voltage/current densities, chemical inertness, biocompatibility and low background/capacitive currents. However, BDD exhibits a relatively poor surface catalytic behavior. We overcame this issue by immobilizing catalysts at the electrode surface using transition metal nanoparticles. Toward this goal, the reactivity of the BDD electrodes was enhanced using transition metals such as platinum, iridium, gold, ruthenium, etc and their corresponding alloys. Their characteristics in terms of size, oxidation levels, and adhesion were well characterized to ensure high stability and reproducibility. These nanoparticles exhibit an interesting electro-catalytic activity and open the way to the detection of products derived from enzymatic reactions, pesticides or many other electrochemically non-active species. We propose a complete multi-sensor detection system based on several BDD electrodes each functionalized using a different catalyst metal in the form of nanoparticles, thus each exhibiting a specific reactivity, enabling the recording of chemical fingerprints of the products to detect in real samples. An advanced algorithmic learning / recognition methods enables the system to behave as an ?electronic tongue?. The approach was applied to several case studies, including hydrogen peroxide, food contaminants such as scatol or indole, nitrate/nitrite pollution of water sources and industrial sites and even much more complex systems such as coffee brands!

V.6.1
09:30
Authors : Osamu Niwa1,2; Tomoyuki Kamata2, 3; Eisuke Kuraya4; Taisei Nishimi5; Masashi Kunitake6; Dai Kato2
Affiliations : Saitama Institute of Technology,1690, Fusaiji, Fukaya, Saitama, 369-0293 Japan1; National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, 305-8566 Japan2; Chiba Institute of Technology,2-17-1 Tsudanuma, Narashino, Chiba 275-0016 Japan3; Okinawa National College of Technology, 905 Henoko, Nago, Okinawa 905-2192 Japan4; ARPChem., 2-11-9, Iwamoto-cho, Chiyoda-ku Tokyo, 101-0032, Japan5; Kumamoto University,2-39-1, Kurokami, Kumamoto, 860-2192 Japan6

Resume : Electrochemical activity of the carbon materials is significantly influenced by surface functional groups. For example, electrochemical pretreatment of carbon electrode drastically increases surface oxygen functional group and improves electrochemical activity for various biochemicals such as catecholamines and L-ascorbic acid. We have been developing nanocarbon film electrodes by using electron cyclotron resonance (ECR) or unbalanced magnetron (UBM) sputtering techniques. The films shows wide potential window because of hybrid structure of sp2 and sp3 bonds and low capacitive current due to very flat surface. We recently prepared nitrogen terminated carbon (NS-UBM) film by ammonia gas treatment after depositing the film by UBM sputtering and compared its electrochemical performances with those of a nitrogen containing carbon (N-UBM) film also deposited by UBM sputtering in the presence of nitrogen gas. The nitrogen concentrations on the surface of both films are almost identical, which is confirmed by XPS measurement. The oxygen reduction at NS-UBM film shifts more positive compared with N-UBM film electrode, suggesting that surface groups are very important to reduce overotential for oxygen reduction. The peak potentials and heights of some redox biomolecules are also compared using above two films. In contrast, a fluorinated nanocarbon (F-nanocarbon) film can be formed by CF4 plasma treatment of pure carbon films. The potential window of the film increases from 3.7 V to 4.1 V and surface capacitance drastically decreased after fluorination This F-nanocarbon film electrode shows much better stability compared with fluorinated GC electrode against repetitive potential cycling. The F-nanocarbon film electrode shows reversible electrochemical reaction of a ferrocene based mediator while strongly suppressing the electrochemical oxidation of Fe2+ due to hydrophobicity of F-nanocarbon surface. This selectivity provided the current amplification of ferrocene mediators with Fe2+ ions by using the F-nanocarbon film electrode without interference from direct oxidation of Fe2+ ions. This system was applied to realize lipopolysaccharide (LPS) biosensor by modifying the F-nanocarbon surface with polymer film to adsorb LPS. After preconcentration of LPS onto the polymer surface, we applied ferrocene labelled polymyxin B to LPS because polymyxin-B strongly recognized LPS. Finally, we detected LPS concentration by selective electrochemical signal amplification.. Since the direct electrochemical oxidation of Fe2+ was almost completely suppressed on the F-nanocarbon film, we can obtained large current amplification by applying high concentration of Fe2+. As a results, the F-nanocarbon film based LPS biosensor shows better linearity particularly at low concentration region due to the suppression of direct Fe2+ oxidation. As a result, the detection limit of 2 ng /ml was obtained. Another application of F-nanocarbon film is to detect lipophilic antioxidant such as??-tocophenol (Vitamin E) quantitatively in bicontinuous microemulsions (BMEs). BMEs, in which water and oil phases coexist bicontinuously on a microscopic scale, can dissolve hydrophilic, lipophilic and amphiphilic compound simultaneously. Electrochemical contact with water or oil solution phases in a BME can be alternatively changed by controlling the hydrophilicity and lipophilicity of the electrode surface. We tried to detect lipophilic and hydrophilic antioxidant selectively using mixed solution of 1 mM ascorbic acid and 1 mM ??tocophenol using indium thin oxide (ITO) and F-nanocarbon electrode. On the hydrophilic ITO electrode, the oxidation peak of L-ascorbic acid was observed even in the presence of ??tocophenol. In contrast, only the peak of ??tocophenol was observed at F-nanocarbon film electrode. This indicates that F-nanocarbon film selectively detect lipophilic antioxidant in the BMEs because only oil phase containing ??tocophenol is contact phase on the F-nanocarbon film electrodes. This BME-EC technique can applied for quantitative analysis of antioxidants in olive oils and exhibited a reliable and good performance that are comparable with conventional instrumental analysis. The lack of an extraction step in our method is a major improvement compared with other assays.

V.6.2
10:00
Authors : Takahisa Tanaka1, Takamune Yokoyama1, Yoshihiko Shimokawa1, Ryosuke, Yamachi1, Akihito Goto1, Tsunaki Takahashi2, Ken Uchida1
Affiliations : 1 Keio University, Yokohama, Japan; 2 Kyusyu University, Kasuga, Japan

Resume : Graphene has attracted much attention as a chemical sensor material because of its high sensitivity to surface adsorbates. Decoration of Pd nanoparticles on graphene has been widely used to acquire hydrogen sensitivity. However, effects of gate-induce electric field on sensitivity of Pd nanoparticles decorated graphene (Pd-Gr) have not yet been fully investigated. In this work, sensitivity enhancement of Pd-Gr induced by gate electric field is experimentally and numerically demonstrated. Gate voltage dependence of hydrogen sensitivity or current change between drain current with and without hydrogen were measured. Obtained hydrogen sensitivity is much higher in the electron conduction than in the hole conduction. The sensitivity difference between electron and hole conduction regimes in Pd-Gr was numerically analyzed by non-equilibrium Green function calculations. The decoration of Pd nanoparticles causes the local hole doping to graphene. This local hole doping disturbs electron transport more severely than hole transport, because p-type region originated from local hole doping acts as a potential barrier for electron. When hydrogen is introduced, adsorbed hydrogen atoms generate dipoles at the surface of Pd nanoparticles. These dipoles compensate the local hole doping caused by Pd nanoparticles, and thus the degraded electron transport is recovered, resulting in the higher hydrogen sensitivity in the electron conduction.

V.6.3
10:15
Authors : Y. Shimokawa [1], R. Yamachi [1], A. Goto [1], G. Takeuchi [1], T. Yokoyama [1], Y. Saito [1], T. Tanaka [1], T. Takahashi [2], K. Uchida [1]
Affiliations : [1] Keio University, Yokohama, Kanagawa, Japan; [2] Kyusyu University, Kasuga, Japan

Resume : Human breath contains a lot of volatile organic compounds (VOCs). Since VOCs are potential markers of diseases, gas sensors targeting VOCs have attracted great attention. Graphene is composed of six-membered ring structures; graphene strongly captures aromatic compounds with ?-? interaction. Furthermore, graphene has high surface-to-volume ratio. These properties make graphene a promising material for selective and sensitive sensing of aromatic compounds. However, sensing properties of graphene for VOCs other than aromatic compounds have not yet been fully explored. In this study, sensing properties of Pt-functionalized graphene for aliphatic alcohol were investigated. Sensor was measured at temperatures ranging from room temperature to 200 °C. To evaluate gas detection capability of the sensor, hydrogen and ethanol were used. We confirmed that Pt functionalization enhanced sensitivity to both hydrogen and ethanol. Sensitivity of hydrogen did not show temperature dependence, while ethanol showed higher sensitivity as temperature increases. This is considered to be due to an increased decomposition of hydroxyl group by Pt catalysis and greater hydrogen release at higher temperatures. Then, we measured alcohols with different numbers of carbons. Although concentration was constant, sensitivity increases as the number of carbon atoms of the alkyl chain. This probably arises from a greater adsorption of longer alkyl chain to graphene because of stronger hydrophobic interactions.

V.6.4
10:30
Authors : Yan Yuan*, Rongjin Zhang, Cong Li, Zhiquan Li
Affiliations : The Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, School of chemical and material engineering, Jiangnan University

Resume : added into UV-curable polyurethanes to form flexible conductive coating on PET plate via spin-coating and UV exposure. The microstructure of composite and coatings were investigated by TEM and SEM. The coatings were stripped from PET plate and assembled as humidity sensor. The sensor exhibited superior humidity sensing properties with wide response range(0.15%-69.52%), short response/recovery time(32s/54s), excellent repeatability and flexibility. The resistance of sensors is nearly invariable after 200 folding times. The results demonstrated the has the potential application to humidity sensors.

V.6.5
10:45 Coffee break    
 
Energy II : Wenjun Zhang
11:00
Authors : Robert Dryfe, Andinet Ejigu, Ian Kinloch, Hollie Patten
Affiliations : Universitybof Manchester

Resume : The electrochemical properties of graphene, and related 2D materials (notably MoS2), will be discussed. Electrochemical methods can be used to prepare, and to functionalise , these materials. We will discuss our recent work on the development of a simultaneous exfoliation/functionalisation strategy. We will also discuss how such functionalised materials can be used to optimise performance of 2d materials in the context of electrochemical energy storage.

V.7.1
11:30
Authors : Anke Krueger,* Benjamin Kiendl, Andreas Muzha, Steffen Heyer
Affiliations : Institute for Organic Chemistry, Julius-Maximilians-University Wuerzburg, Wuerzburg, Germany

Resume : The efficient storage and supply of energy from renewable resources is a worldwide challenge and requires efficient and fast energy storage devices. Technologies such as lithium ion and other battery systems are already widespread. Carbon materials are another promising class of materials for energy storage, e.g. in batteries and supercapacitors. Another important area of research is the generation of solar fuels using benign and readily available catalysts for the transformation e.g. of carbon dioxide into useful chemicals and building blocks. Here we report on the production, characterization of surface functionalized nanodiamond of different origin. The resulting nanodiamond derivatives can be used as additives in supercapacitor materials, as heterogenized organocatalysts as well as for the photocatalytic generation of solar fuels. Challenges such as the stable surface modification and the agglomeration of nanoparticles will be addressed. This project has received funding from the European Union's Horizon2020 research and innovation programme under Grant Agreement no. 665085 and the "Bayerisches Staatsministerium für Umwelt und Verbraucherschutz? in the network UMWELTnanoTECH (http://www.umwelt-nanotech.de).

V.7.2
12:00
Authors : Jing Xu, Nianjun Yang, Yusi Yu, Steffen Heuser, Xin Jiang
Affiliations : Jing Xu, Institute of Materials Engineering, University of Siegen; Nianjun Yang, Institute of Materials Engineering, University of Siegen; Yusi Yu, Institute of Materials Engineering, University of Siegen, Steffen Heuser; Institute of Materials Engineering, University of Siegen; Xin Jiang. Institute of Materials Engineering, University of Siegen

Resume : While boron-doped diamond (BDD) and TiO2 have been recognized as attractive electrodes and photo-catalytic materials, the composite films consisting of TiO2 and BDD are potential (photo)electrode materials for various applications. On these electrodes, a so-called advanced oxidation process, namely the creation of highly active oxidants or radicals is expected, resulting in the rapid and efficient decomposition of aqueous organics and contaminants. However, the growth and electrochemical applications of such kind of composite films are seldom reported in the literature, partly due to the difficulties of material preparation. In this presentation, we introduce a novel approach to synthesize TiO2/BDD composite films. plasma electrolytic oxidation (PEO) is combined with microwave-assisted chemical vapor deposition (MWCVD) technique for the growth of these films. The investigation of the formation of porous TiO2 film on the Ti substrate and the overgrowth of TiO2 with BDD films will be shown. The achievement of different phase compositions (the varied ratios of TiO2 to BDD on the surface) by altering CVD growth time will be presented. The characterization of the surface morphology and chemical compositions of as-prepared samples with scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy will be summarized. The application of Rockwell C indentation to examine their mechanical properties will be presented. The SEM images reveal full filling of TiO2 pores with BDD. Compare to direct deposition on substrates, a better adhesion strength is found between diamond and metal substrate after PEO pretreatment. The formed TiO2 interlayers are expected to reduce the diffusion of carbon species and the formation of TiH2 phase, eventually causing the embitterment of Ti substrates and leading to the reduction of the mechanical performance. The investigation of electrochemical properties of these composite films with respect to potential windows, electrochemical activity, and capacitance will be summarized. Their potential applications in the fields of electrochemical capacitors and photoelectrochemistry will be shown and discussed.

V.12.7
12:15
Authors : Haifeng Dong,Chengya Ru
Affiliations : Research Center for Bioengineering and Sensing Technology,Beijing Key Laboratory for Bioengineering and Sensing Technology, School of Chemistry and Biological Engineering, University of Science & Technology Beijing, 100083, China

Resume : Abundance and low-cost materials with high electrochemical catalytic activity for oxygen reduction reaction (ORR) are in urgent demand for energy storage and conversion devices. In this work, an efficient ORR electrocatalyst of Pt-decorated three dimensional N-doped carbon microspherical cavity (Pt-N/C) for advanced ORR catalyst by using polystyrene (PS) as template and dopamine as a single precursor. Electrochemical characterizations showed good performance of Pt-N/C including excellent ORR catalytic activity, remarkable methanol tolerance and good durability in alkaline solutions. It revealed that the numerous Pt nanoparticles strongly decorated on carbonous substrate coupling with the doped nitrogen synergistically allowed to the advanced catalytic activity, while the unique 3D microspherical porous morphology facilitated the oxygen adsorption and mass transfer. Importantly, the strong Pt-C interaction due to the powerful adhesive capability of dopamine effectively reduced the amount of Pt and provided better mass activity (MA) and specific activity (SA) than the commercial Pt/C electrocatalyst. This work provided a strategy for designing advanced Pt-based ORR catalyst with good performance and high MA.

V.7.4
12:30
Authors : Kaikai Zhang, Peng Sun, Yanrong Zhang
Affiliations : K Zhang; Yanrong Zhang; Environmental Science Research Institute, Huazhong University of Science and Technology; P Sun; Environmental Science Research Institute, Huazhong University of Science and Technology; School of Energy and Environment, Inner Mongolia University of Technology;

Resume : The study investigated the properties of biochar and its potential in chlorobenzene degradation. Biochar was derived from rice husk and charred at 550? in N2 atmosphere, which showed a significant degradation of chlorobenzene in ambient atmosphere. The results from Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD) and Raman spectroscopy (Raman) indicated the formation of poorly ordered graphene stacks embedded in amorphous phases on biochar. Fourier Transform Infrared Spectroscopy (FTIR) and Electron Paramagnetic Resonance (EPR) suggested that hydroquinone-quinone moieties existed on biochar, which could induce the generation of reactive oxygen species (ROS) and promote degradation of chlorobenzene. Furthermore, hydrogen peroxide and hydroxyl radicals were generated from the reduction of oxygen with the oxidization of phenolic hydroxyl groups on biochar, which was responsible for chlorobenzene degradation. In addition, more types of intermediate products were discovered by biochar system compared with conventional Fenton reaction, which could be possibly ascribedto the interfacial reaction between chlorobenzene and ROS on biochar surface. The findings in this study would provide new insights into the application of biochar in pollutant removal.

V.7.5
12:45 Lunch break    
 
Catalysts II : Paula Colaviata
14:00
Authors : Giovanni Valenti, Alessandro Boni, Massimo Marcaccio, Stefania Rapino, Matteo Iurlo, Francesco Paolucci
Affiliations : Department of Chemistry Giacomo Ciamician, University of Bologna, via Selmi 2 40126 Bologna, Italy

Resume : Nanomaterials are nowadays at the forefront of materials science research. The design and realization of hierarchical nanoarchitectures, in which selected components are arranged to leverage their expected mechanistic functions are obtaining a wide range of applications, from the aerospace industry to bio-medicine, and as benchmarks for many catalytic reactions. Carbon-based nanomaterials have been the main actors of nanotechnology since their very first discovery, and their unique morphological/electronic properties are particularly suited to be used in electrocatalytic applications. CNTs and graphene are indeed ideal supports in catalysis as they have an optimal electronic conductivity and provide percolation routes for charge transfer reactions to occur. The integration of nanocarbons into hierarchical materials is an effective strategy to further boost the potentiality of nanostructured catalysts. The generation of multiple interfaces in such hierarchical assemblies is responsible for their exceptional activity, whose origin is however only rarely understood. We will show that, once embedded within nanoarchitectures made of multi-wall carbon nanotubes or graphene and metal oxide shells, the catalytic properties of nanoclusters (1,2) and metal nanoparticles (3,4) can be dramatically enhanced according to mechanisms which likely involve the concerted and synergic participation of all component building blocks in the electrocatalytic steps. References (1) F.M. Toma et al., Nature Chemistry 2010, 2, 826 (2) M. Quintana et al. ACS Nano 2013, 7, 811?817 (3) R. Mazzaro et al. ChemistryOpen 2015, 4, 268 ? 273 (4) G. Valenti et al. Nature Communications 2016, 7 DOI: 10.1038/ncomms13549

V.8.1
14:30
Authors : Wei Chen
Affiliations : Department of Physics National University of Singapore, Singapore 117542, Singapore Department of Chemistry, National University of Singapore, 117543, Singapore

Resume : Understanding and controlling the growth of the vital Li2O2 product, which is associated with intrinsic property of cathode surface, is essential to design effective cathode catalysts in Li-O2 batteries. Herein we establish the correlation between the Li2O2 growth model and the O2 adsorbability on cathode surface that determines the pathway of the first electron transfer to O2. The weak O2 adsorbability drives the solution growth model to form Li2O2 toroid, while the strong one drives the surface growth model to thin film. Based on this mechanism, we select the N-doped carbon nanocages as cathode to realize a simultaneous large discharge capacity and low charge overpotential by forming copious thin-film Li2O2, deriving from its high specific surface area and enhanced O2 adsorbability due to N-doping. Our study demonstrates an effective strategy to design advanced cathode catalysts in Li?O2 batteries and potentially other metal-air batteries. Reference: ?Effect of oxygen adsorbability on the control of Li2O2 growth in Li-O2 batteries: implications for cathode catalyst design? Lyu ZY, Yang LJ, Luan YP, Wang XR, Wang LJ, Hu ZH, Lu JP, Xiao SN, Zhang F, Wang XZ, Huo FW, Huang W, Hu Z*, Chen Wei*, Nano Energy. 36, 68-75 (2017) DOI: 10.1016/j.nanoen.2017.04.022

V.8.2
15:00
Authors : Thuan-Nguyen Pham-Truong, Thomas Petenzi, Christine Ranjan, Jalal Ghilane and Hyacinthe Randriamahazaka
Affiliations : ITODYS Laboratory, UMR 7086, Chemistry Department, Paris Diderot University, France

Resume : From the past few years, carbon based nanomaterials (N-doped carbon nanotube arrays, N-doped graphene, N-doped graphene nanoplatelets, etc.) have been widely studied as highly efficient catalyst for the oxygen reduction. Recent studies on microwave assisted method demonstrate a supporting evidence for the formation of carbon quantum dots (CDs) from bio-abundant starting materials as glucose, amino acids, etc. Recently, uniform N doped CDs which shown highlighted results toward ORR were synthetized by one step solvothermal process using bottom up mechanism from N-Methyl-2-pyrrolidone. Although there have been important research focusing on the N-doped carbon dots, their use in electrocatalysis toward oxygen reduction is still scanty. Meanwhile ionic liquids and its derivatives have been started to be used as additive for oxygen reduction. In this context, we develop facile route to synthetized N-doped few nanometer scale CDs by microwave assisted method as high efficient catalyst for ORR. Our studies were demonstrated that the N-doped CDs synthetized in ionic liquid (1-ethyl-3-methylimidazolium) exhibit exceptional selectivity toward 2 electron pathway resulting production of hydrogen peroxide (95% ±2 % over a broad range of potential from 0.6 V to -0.2 V vs RHE). In addition, the N-doped CDs can be used as platform for electrocatalysis by inserting non noble metal ion (Fe, Co, Zn, etc.) or by surface functionalization.

V.8.3
15:15
Authors : Mahir GULEN(1,3)*, Ahmet AVCI(1), Mucahit YILMAZ(2), Savas SONMEZOGLU(3,4)
Affiliations : (1) Department of Mechanical Engineering, Selcuk University, Konya, Turkey (2) Department of Metallurgical and Materials Engineering, Seydisehir Ahmet Cengiz Faculty of Engineering, Necmettin Erbakan University, Konya, Turkey (3) Nanotechnology R&D Laboratory, Karamano?lu Mehmetbey University, 70200, Karaman, Turkey (4) Department of Metallurgical and Materials Engineering, Karamano?lu Mehmetbey University, Karaman, Turkey

Resume : Here, we firstly report a highly efficient dye-sensitized solar cell (DSSC) employing single layer graphene (SLG) and Poly(2,2-Dimethyl-3,4-propylenedioxythiophene) (PProDOT-Me2) nanocomposite as counter electrode (CE). To evaluate the performance of CEs, physical, electrochemical and photovoltaic analyses were conducted. The growth rate of the PProDOT-Me2 polymer increases with incorporation of SLG, introducing more densely packed surface morphology and well adherence of the film on the substrate. Furthermore, the SLG/PProDOT-Me2 nanocomposite-based CE exhibited a vigorous electrocatalytic activity in comparison with that of SLG, PProDOT-Me2 and platinum (Pt) based CEs due to its large surface area and high conductivity. As a result, the SLG/PProDOT-Me2 CE based cell achieved a conversion efficiency of 7.56%, which is considerably higher than that of the SLG (0.63%), PProDOT-Me2 (5.62%) and Pt (7.24%) under same experimental conditions. It is obvious that combining SLG and PProDOT-Me2 reduces the electron transfer resistance and improves the interface of substrate/CE, leading to an increment in photo-current (Jsc), open circuit voltage and fill factor of the cell. Moreover, besides a high conversion efficiency, SLG/PProDOT-Me2 nanocomposite-based CE offers prolonged electron lifetime, fast start/stop capability, high chemical and Jsc stabilities for the proposed DSSC. Hence, outstanding catalytic activity, high stability, facile preparation and low-cost of SLG/PProDOT-Me2 nanocomposite offer it as CE material instead of Pt for large-scale production of photovoltaic systems. Key words: PProDOT-Me2, Graphene, Electrodeposition, Dye-sensitized Solar Cell, Nanocomposites

V.8.4
15:30 Coffee break    
 
Interfaces : Anke Krueger
16:00
Authors : Laia Gines 1*, Soumen Mandal 1, Ashek-I-Ahmed 2, Chia-Liang Cheng 2, Maabur Sow 3, Cesar Magen 4, and Oliver A. Williams1
Affiliations : 1 School of Physics and Astronomy, Cardiff University, UK 2 Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan 3 EPSRC Centre for Doctoral Training in Diamond Science and Technology, Warwick University,UK 4 Laboratorio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA), Universidad de Zaragoza, 50018 Zaragoza, Spain

Resume : It is well known that diamond nanoparticles' surface charges play a determining role in view of its subsequent material characteristics. Surface charges are determined by the surface functional groups present in the diamond nanoparticles, and can be controlled through different cleaning methods, annealing treatments or surface functionalization. The manipulation of these surface charges will be deeply important for a wide range of applications and will have an important influence over colour centres fluorescence. However, for most applications, diamond nanoparticles have to exhibit stability in colloidal systems to prevent particles? aggregation. The key indicator of a colloid stability is known as zeta potential and is defined as absolute zeta potential values greater than 30mV. Diamond nanoparticles usually exhibit negative zeta potentials due to oxygen based surface functional groups, but hydrogenated diamond nanoparticles were proved to have a positive zeta potential although the origin was uncertain. In this work, the positive zeta potential of commercial 50 nm size diamond nanoparticles after vacuum annealing treatments at 1000°C is explained. At this temperature, a graphitic layer is created around the diamond core of the diamond nanoparticles. Positive zeta potential in nano- structured carbons is explained due to the presence of basal planes in graphite, which leaves oxygen-free Lewis sites and so promotes the suppression of acidic functional groups. At the same time, sp2 carbon creation on diamond nanoparticles surface eases low temperature (500°C) diamond nanoparticles hydrogenation, previously demonstrated for detonation diamond (5nm).

V.9.1
16:30
Authors : Diby Benjamin Ossonon, Daniel Bélanger
Affiliations : Université du Québec à Montréal Département de Chimie Case Postale 8888, succursale Centre-Ville Montréal (Québec) Canada H3C 3P8

Resume : We have recently reported that graphene sheets can be spontaneously functionalized with anthraquinone molecules in a one-pot process, during the oxidative electrochemical exfoliation of a graphite electrode in a 0.1 M H2SO4 solution containing anthraquinone diazonium ions (Carbon, 2017, 111, 83-93). Electrochemical exfoliation of graphite in only the abovementioned solution afforded graphene sheets with low oxygen content. In this talk, new results related to the characterization of the electrochemical exfoliation process will be presented. As mentioned above, graphene sheets can be functionalized during the electrochemical exfoliation process by using appropriate reagents and experimental conditions. The resulting materials were characterized by several techniques such as Fourier transform infrared, X-ray photoelectron and Raman spectroscopy, thermogravimetric analysis, elemental analysis, electronic conductivity measurements and electrochemical techniques. Recent results on both processes (electrochemical exfoliation and simultaneous functionalization during electrochemical exfoliation) will be presented.

V.9.2
16:45
Authors : Xuefeng Lu, Peng Xiao
Affiliations : 1. State Key Lab. for Powder Metallurgy, Central South University, Changsha, 410083, PR China 2. Key Lab. for Eco-textiles, Ministry of Education, Jiangnan University, Wuxi, 214122, PR China

Resume : Carbon nanofibers (CNFs) and Silicon carbide nanofibers (SiCNFs) used as the second reinforcements of carbon/carbon (C/C) composites were grown radially on the carbon fiber surface, respectively. The microstructure of SiCNFs and their effects on the interfacial structure and thermal conductivity of C/C composites were investigated. Results show that pyrocarbon (PyC) covered on CNFs is high-texture (HT) PyC, and there is a interface layer between fiber and matrix consists of middle-texture (MT) PyC and CNF HT-PyC. MT-PyC is first covered on the SiCNF surface, which is followed by HT-PyC. The interface layer between carbon fibers and matrix is composed by SiCNFs, MT-PyC and HT-PyC. These different interfacial structures are leading to the change of thermal conductivity of C/C composites in different direction. The thermal conductivity of CNF-C/C composites increases more significantly in the direction perpendicular to carbon fiber than the direction parallel to fiber. However, the thermal conductivity of SiCNF-C/C composites increases more significantly in the parallel direction than in the perpendicular direction.

V.9.3
17:00
Authors : Shuhei Naoi (1), Keisuke Natsui (1), Takeshi Watanabe (2), Hiroshi Nagasaka (3), Yasuaki Einaga (1) (4)
Affiliations : (1) Department of Chemistry, Keio University, Japan; (2) Department of Electrical Engineering and Electronics, Aoyama Gakuin University, Japan; (3) Tokyo Metropolitan Industrial Technology Research Institute, Japan; (4) JST-ACCEL, Japan

Resume : Boron-doped diamond (BDD) electrodes have attracted considerable attention due to their excellent electrochemical properties, and they have been utilized for the electrochemical applications such as wastewater treatment and electrochemical sensors. On the other hand, BDD electrodes have been prepared mainly by two kinds of chemical vapor deposition (CVD) methods: a microwave plasma-assisted (MP) method and a hot filament (HF) method. However, there are few reports comparing the electrochemical properties of BDD electrodes prepared by these two CVD methods. In this study, we have prepared and investigated several kinds of BDD electrodes with different boron concentration using MPCVD and HFCVD methods to compare the electrochemical properties of them systematically. The electrochemical properties of BDD electrodes were examined by cyclic voltammetry (CV) measurements in an aqueous solution of 1 mM potassium ferricyanide and 1 M KCl. From the CV curves, the anodic and cathodic peak separation increased with decreasing boron concentration. Furthermore, the values of the peak separation were different between BDD prepared by MPCVD (BDD-MP) and BDD prepared by HFCVD (BDD-HF), even though they had almost the same boron concentration. In case of the high boron concentration, the peak separation on BDD-HF was larger than that on BDD-MP. On the other hand, in case of the low boron concentration, the opposite tendency was observed. To reveal the mechanism of these trends, we are currently investigating the electrical and structural properties.

V.9.4
17:15
Authors : Xin Liu, Yuhan Zhu, Kai Yan, Jingdong Zhang*
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, P.R. China

Resume : Photovoltammetric behaviors of different reversible reaction systems including 2.4-chlophenol (DCP), hydroquinone (HQ) and K3[Fe(CN)6] were investigated on a hybrid film prepared with CdS quantum dots and low content of graphene (G). The cyclic voltammetric (CV) curves of HQ and K3[Fe(CN)6] showing a pair of redox peaks became sigmoidal in shape under visible light illumination. In contrast, the CV curve of DCP showing an oxidation peak did not change in shape under the illumination. This result revealed the reversibility-dependent photovoltammetric curve shape, despite of enhanced oxidation currents in all the three reaction systems due to photoelectrocatalysis. Furthermore, we studied the photovoltammetric behaviors of three reaction systems at different pH values, scan rates, intensities of light source and concentrations of reactant. It was observed that that the photovoltammetric curve shape was not changed by pH and intensity of light source, but was tunable with scan rate and concentrations of reactant.

V.9.5
17:30
Authors : Soumen Mandal1, Evan Thomas1, Joshua Green1, Laia Gines1, Emmanuel Brousseau2, and Oliver Williams1
Affiliations : 1School of Physics and Astronomy, Cardiff University, Cardiff, UK 2School of Engineering, Cardiff University, Cardiff, UK

Resume : Micro-electrical mechanical systems incorporate the actuation, perturbation, and sensing of micron level mechanical devices within electronic circuits. They can be used to detect mass1, force2 and displacement. Ultra-sensitive detection of these parameters is important for many bio-medical applications3,4. Apart from ultra-sensitive nature of detection it is important to have the detectors made out of materials which are bio-inactive, making diamond an excellent candidate for such devices due to its bio-compatibility5. While thin film diamond can be grown in both single-crystal and polycrystalline forms, the retention of many of the properties of bulk diamond and possibilities of large area deposition make nano-grained nanocrystalline diamond (NCD) a viable alternative. However, the downside of the NCD is the inherent surface roughness that comes due to its growth mechanism6. Palasantzas7 have shown that surface roughness in a mechanical devices can lead to reduced sensitivity. To get around this problem we have developed a chemical mechanical polishing technique capable of generating smooth diamond surfaces, however the rate of polishing is extremely slow (20nm/h). In this work, we explore the effects of addition of strong oxidizing agents to the polishing fluid on the roughness reduction rate of diamond films. A series of diamond films were grown on silicon dioxide buffered silicon using CVD. The films were polished for four hours and the roughness monitored by atomic force microscopy after each hour of polishing. The base slurry for polishing was colloidal silica based SF1 from Logitech. The slurry could reduce a nominal roughness of ~24nm RMS on as grown diamond films to ~2nm RMS over 25 µm2 within four hours of polishing. The same slurry with trace amounts of Fe(NO3)3 or KMnO4 could polish the films to ~2nm RMS roughness with just 2 hours of polishing clearly indicating an increased polishing rate. Similar enhancement was not seen for slurry with hydrogen peroxide. References 1 K. Jensen, K. Kim, and A. Zettl, Nat. Nanotechnol. 3, 533 (2008). 2 J. Moser, J. Güttinger, a Eichler, M.J. Esplandiu, D.E. Liu, M.I. Dykman, and a Bachtold, Nat. Nanotechnol. 8, 493 (2013). 3 K.J. Rebello, Proc. IEEE 92, 43 (2004). 4 S. Bhansali and A. Vasudev, editors , MEMS for Biomedical Applications (Woodhead Publishing Limited, Sawston, Cambridge, UK, 2012). 5 L. Tang, C. Tsai, W.W. Gerberich, L. Kruckeberg, and D.R. Kania, Biomaterials 16, 483 (1995). 6 O.A. Williams, Diam. Relat. Mater. 20, 621 (2011). 7 G. Palasantzas, Appl. Phys. Lett. 90, 1 (2007).

V.9.6
17:45
Authors : Haiyuan Fu, Hao Zhuang, Siyu Yu, Nianjun Yang, Xin Jiang
Affiliations : Institute of Materials Engineering, University of Siegen, Paul-Bonatz-Str. 9-11, 57076 Siegen, Germany

Resume : Due to their desirable physical and chemical properties, porous 3C-SiC films are a fascinating structure among all potential 3- and low dimensional structures of SiC. In this work, we demonstrate a feasible, controllable, and ?template-free? approach to fabricate porous 3C-SiC thin films, which combines the deposition of diamond/?-SiC composite films with a subsequent high temperature selective oxidation step of the diamond phase. Following this approach, porous 3C-SiC films with different crystallite sizes are obtained. The porosity of these films can be tuned by controlling the amount of the diamond phase in the composite films. The effect of high temperature heating on the SiC films is investigated, which, in turn, allows to identify the optimum temperature for preparing porous 3C-SiC films. SEM, Raman measurements and electrochemical tests are carried out to characterize the films before and after the oxidation process. The porous films fabricated in this way showed strongly increased capacitance compared to pure SiC films rendering them ideal candidates for numerous potential applications in the field of sensors, bio-interfaces and filters.

V.9.7
18:00
Authors : Melissa Pirie, Luyun Jiang, Seong Ok Han, John S. Foord
Affiliations : Department of Chemistry, University of Oxford , South Parks Road, Oxford, OX1 3TA, UK; Department of Chemistry, University of Oxford , South Parks Road, Oxford, OX1 3TA, UK; Energy Materials Research Laboratory, Korea Institute of Energy Research, Daejeon 305-343, Korea; Department of Chemistry, University of Oxford , South Parks Road, Oxford, OX1 3TA, UK

Resume : Supercapacitors are high power energy storage devices with long cycling lifetimes that are generally safe and reliable. Supercapacitors typically use aqueous electrolytes as charge carriers. An alternative to these are solid state gel electrolytes, which result in supercapacitors that are flexible, less likely to leak and safer to use. Currently, commercial supercapacitors are made from materials that generally are not environmentally friendly. Carbonised biomass is an alternative material that is receiving increasing amounts of interest, as it is renewable, environmentally friendly, and relatively cheap to produce. Seaweed fibre is a natural, abundant cellulose material with uniform dimensions ten times smaller than other plant-based fibre. In this work we converted seaweed fibre into a functionalised carbon material by a thermal carbonisation method, and then developed a novel method to manufacture a high capacitance solid state supercapacitor. A sound performance was obtained by using KOH and poly(vinyl alcohol) (PVA) as an electrolyte. However the supercapacitance deteriorated significantly with increasing charge-discharge cycles. To improve the stability, ionic liquid/PVA electrolytes were used. After 1000 cycles a GCD showed that over 90 % of the original capacitance was retained.

V.P2.1
 
Poster Session II : Osamu Niwa, Robert Dryfe, Quan Xie
18:00
Authors : Min Wang, Songwei Li, Yongfu Lian*
Affiliations : Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, China.

Resume : Ni hydroxides is one of the multitudinous promising electrochemical capacitors materials due to its high capacitance, relatively low-cost, almost pollution-free and good redox activity. On the other hand, graphene has attracted lots of attention also for potential electrochemical capacitors owing to its outstanding electrochemical stability, large specific surface area and high conductivity. In our work, the graphene doped Ni(OH)2 nanoflims are deposited on the Nickel Foam’s porous framework via a simple solvothermal process. The as-prepared graphene doped Ni Hydroxides and nickel foam ternary composite (named GNOH /NF) electrode exhibits a good specific capacitance of 1951.1 F.g-1 at current density of 1 A/g. And the specific capacitance still remains 772.6 F.g-1 (39.6 % compared with its initial 1 A/g) at a very high current density of 40 A/g, the ternary composite electrode also demonstrates excellent flexibility and stable cycle lifetimes (almost no capacitance loss after 500 cycles). Additionally, the asymmetric supercapacitor is successfully assembled by using GNOH /NF as the positive electrode and reduced graphite oxide deposed on nickel foam (rGO /NF) as the negative electrode. The GNOH /NF // rGO /NF device exhibits a relatively high energy density of 22.5 Wh kg -1 at a power density of 4.0 kW kg -1 with excellent cycling performance( 107.6 % capacitance retention over 1000 cycles), and we believe it is a promising candidate for energy storage devices.

V.P2.2
18:00
Authors : Xiaodong Cao, Keqin Liu, Xueting Zhu, Shudong He, Hanju Sun, Yongkang Ye*
Affiliations : School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China *e-mail: yongkang.ye@hfut.edu.cn

Resume : In this paper, we developed an electrochemical sensor for rapid detection of phoxim in marine products based on a zirconium dioxide (ZrO2) nanoparticles decorated hemin functionalized reduced grapheme oxide (hemin-rGO) modified grassy carbon electrode (ZrO2/hemin-rGO/GCE). The surface of modified electrode was characterized by TEM, UV-vis spectroscopy and XPS, and the electrochemical behavior of phoxim at the modified electrode was studied by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and chronocoulometry. The ZrO2/hemin-rGO/GCE was applied to the selective amperometric detection of phoxim at a working potential of -0.2 V (vs. Ag/AgCl) in pH 6.0 PBS. Under optimized conditions, the cathodic peak current was proportional to the phoxim concentration over a wide range of 0.03 ? 1.5 ?M, with a detection limit of 1×10^-10 M (S/N = 3). The proposed phoxim electrochemical sensor also exhibited a relative standard deviation (RSD) of 4.8% for a seven-replicate analysis of 5 ?M phoxim, and the response of the electrode declined by 5.0% after 9 days at ambient temperature. The results indicate that amperometric method has the potential in rapid and sensitive detecting phoxim residue in marine products.

V.P2.3
18:00
Authors : Yongkang Ye, Yaqian Liu, Shen Mao, Shudong He, Hanju Sun, Xiaodong Cao*, Yingwang Ye*
Affiliations : School of Food Science and Engineering, Hefei University of Technology, Hefei 230009, China *e-mail: xiaodongcao@hfut.edu.cn; yeyingwang04@126.com

Resume : Salmonella is one of the main pathogens which cause human foodborne disease. In this work, an electrochemical biosensor is developed for detection of invA gene of Salmonella based on hairpin assembly target recycling amplification strategy without nuclease and excellent composite of polypyrrole (PPy), reduced graphene oxide (rGO) and gold nanoparticles (AuNPs). A one-step electrochemical approach for fabrication of PPy?rGO?AuNPs nanohybrid composite onto a glassy carbon electrode (PPy?rGO?AuNPs/GCE) is described. PPy?rGO?AuNPs/GCE has a good ability of accelerating electron transfer and provide specific surface area to immobilize thiol-modified hairpin DNA strand 1 (S1) through Au-S affinity. The presence of target invA gene DNA can open hairpin S1 which lead hairpin assembly reaction, therefor the target DNA cycle constantly and biotin label hairpin S2 be fixed increasingly through DNA chain displacement process, so as to combine more HRP to the electrode by affinity interaction of biotin-avidin. Duel strategy amplifies final electrochemical response signal of catalytic reaction of hydrogen peroxide. The developed biosensor provides a composite mode between nanohybrid composite and enzyme-free target recycling strategies thus opens a promising avenue for the detection of ultra-low abundance invA gene of Salmonella in bioanalysis and clinical research.

V.P2.4
18:00
Authors : Yunhui Xiang, Hui Liu, Jie Yang, Zhen Shi, Yuanbin Tan, Jing Jin, Rui Wang, Shenghui Zhang*, Jinshou Wang*
Affiliations : Department of Chemistry, Hubei University for nationalities

Resume : Two-dimensional, graphene-like, membranous structure porous carbon (2DPCs) were prepared via a one-pot, template-free pyrolysis process at 500 (2DPC500), 600 (2DPC600), 700 (2DPC700), 800 (2DPC800) and 900 (2DPC900), which have bifunctional applications in adsorption and electrochemistry. The morphology, structure and property of the composite were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 physisorption analysis and electrochemical methods. 2DPC800 displays a highest surface area (2540 m2g-1) and, for water remediation, displayed high adsorption capacities towards environmental hormone of hydroquinone (HQ, 403 mg g-1) and catechol (CA, 376mg g-1) solutions. Used as an electrode material for simultaneous determination of HQ and CA, 2DPC800 not only showed the highest sensitivity, but also displayed surprisingly lowest detection limit. These results suggest low-cost and green carbon materials as an electrode material for simultaneous determination of HQ and CA, metal-free adsorbents for high efficient removal of hardly degradable contaminants in aqueous solution.

V.P2.5
18:00
Authors : Yao Ma, Nianjun Yang,a,*, Xin Jiangb,*
Affiliations : Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany a nianjun.yang@uni-siegen.de, b xin.jiang@uni-siegen.de

Resume : Carbon nanostructures with precisely controlled shapes are difficult to be synthesized. In this presentation, we propose a facet-selectivecatalytic process to synthesize polymer-like carbon nanostructures with different shapes. A thermal chemical vapor deposition process was applied to grow these multi-branched carbon nanostructures at temperatures lower than 350 oC. Cu nanoparticles were utilized as the catalyst and acetylene as the reaction gas. The growth of those multi-branched nanostructures was realized through the selective growth of polymer-like sheets on certain indexed facets of Cu catalyst. In this way, straight carbon nanofibers (CNFS), carbon nano Y-junction, carbon nano-hexapus, and carbon nano-octopus were obtained [1]. The vapor–facet–solid (VFS) mechanism, as a new growth mode, has been proposed to interpret such a growth, which contains the steps of formation, diffusion, and coupling of carbon-containing oligomers, as well as their final precipitation to form nanostructures on the selective Cu facets [1,2]. Further synthesis of carbon nanofibers (CNFS)/Co(OH)2 nanocomposites was conducted in ethanol at 50 V for 2 min onto gold electrodes. The formed CNFS/Co(OH)2 matrix was characterized by X-ray photoelectron spectroscopy, scanning electron microscopy and cyclic voltammetry. Its electrocatalytic properties towards the oxidation of glucose in 0.1 M NaOH were tested. A detection limit of 5 mM with the linearity in the range of of 10 mM to 0.12 mM was obtained [3]. [1] Y. Ma, X. Sun, N. Yang, J. Xia, L. Zhang, X. Jiang, Chemistry - A European Journal, 2015, 21(35), 12370 - 12375. [2] Y. Ma, C. Weimer, N. Yang, L. Zhang, T. Staedler, Xin Jiang, Materials Today Communication, 2015, 2, e55-e61. [3] Q. Wang, Y. Ma, X. Jiang, N. Yang, Y. Coffinier, M. Li, R. Boukherroub, S. Szunerits, Electroanalysis, 2016, 28(1), 116-125.

V.P2.6
18:00
Authors : Xiaofeng Huang1, Qi Shen1, Jibo Liu1, Nianjun Yang,2,*, Guohua Zhao1, Xin Jiang2
Affiliations : 1 School of Chemical Science and Engineering, Tongji University, 200092, Shanghai, China 2 Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany a nianjun.yang@uni-siegen.de

Resume : Carbon electrodes have the advantages of being chemically inert at negative potential ranges in all media and high offset potentials for hydrogen evolution in comparison to metal electrodes, and therefore are the most suitable electrodes for electrochemistry and electrochemical conversion of CO2 into valuable chemicals [1]. In this presentation, we summarize on carbon electrodes the voltammetry, electrochemical and electrocatalytic CO2 reduction, as well as electron synthesis using CO2 and carbon electrodes. The photoelectrochemical CO2 conversion using a CO2 adsorption-enhanced semiconductor/metal-complex hybrid photoelectrocatalytic interface will be highlighted. In such an interface, a carbon aerogel is employed as the CO2 fixation substrate, Co3O4 as the light harvester, and Ru(bpy)2dppz as the electron transfer mediator and CO2 activator. The CO2 surface concentration exhibits a 380-fold increase on this hybrid interface than that on Co3O4/FTO. The CO2 conversion to formate occurs at an onset potential of -0.45 V (vs. normal hydrogen electrode, NHE) under photoelectrochemical conditions, 160 mV more positive than its thermodynamic redox potential. At an applied potential of -0.60 V (vs. NHE), the selectivity of the formate yield reaches 99.95%, with a production rate of approximately 110 μmol cm-2 h-1, a faradaic efficiency of 86%, and and an electron transfer rate of 2.94×10-3 cm s-1. An instantaneous proton-coupled electron transfer process is confirmed during such a conversion. This originates from the rapid photoelectrochemical activation of bpy and dppz in Ru(bpy)2dppz as well as the synergic effect from the promoted CO2 adsorption and the applied molecular catalysis [2]. [1] N. Yang, S. R. Waldvogel, X. Jiang, ACS Applied Materials and Interface, 2016, 8(42), 8357-28371. [2] X. H. Q. Shen, J. Liu, N. Yang, G. Zhao, Energy Environ. Sci., 2016, 9, 3161-3171.

V.P2.7
18:00
Authors : Qin Wan,a,* Hui Cai,a Yi Liu,a Beibei Li a, Xi Luo a, Zhipeng Qiu a, Dandan Su,a Nianjun Yangb
Affiliations : a School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430073, China b Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany a E-mail: qijinwan@wit.edu.cn

Resume : In most of graphene based electrochemical applications, graphene nano platelets (GNPs) have been applied. In our studies, we investigate first electrochemical properties of GNP regarding its electrochemical activity, potential window, and double-layer capacitance. These properties are compared with those of carbon nanotubes (CNTs) [1]. The GNP is then functionalized with metal nanoparticles [2,3], and small linker molecules [4], and big molecules [5,6]. These interfaces were characterized using various techniques such as SEM, AFM, XPS, and electrochemical techniques. They were further applied for sensing endocrine disrupting chemicals [1,3,6] and small-sized ions [4], oxidation of hydrazine [2], and for biosening [5] . The results confirm that GNP is thus more promising than CNT for electrochemical applications, e.g. for electrochemical detection and removal of endocrine disrupting chemicals. [1] Q. Wan, H. Cai, Y. Liu, H. Song, H. Liao, S. Liu, N. Yang, Chemistry – A European Journal, 2013, 19(10), 3483-3489. [2] Q. Wan, Y. Liu, Z. Wang, W. Wei, B. Li, J. Zou, N. Yang, Electrochemistry Communication, 2013, 29, 29-32. [3] D. Su, Y. Zhang, Z. Wang, Q. Wan, N. Yang, Carbon, 2017, 117, 313-321. [4] Z. Qiu, J. Yu, Y. Peng, Z. Wang, Q. Wan, N. Yang, ACS Applied Materials and Interface, 2016, 8(42), 28291-28298. [5] X. Luo, Z. Qiu, Q. Wan, H. Shu, N. Yang, Phys. Status Solidi A, 2014, 211(12), 2795-2800. [6] B. Li, Z. Qiu, Q. Wan, Y. Liu, N. Yang, Phys. Status Solidi A, 2014, 211(12), 2773-2777.

V.P2.8
18:00
Authors : Otieno Kevin Okoth, Jingdong Zhang*
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, P.R. China

Resume : Gold nanoparticles (Au NPs) and graphene doped CdS (GR-CdS) were employed to fabricate a PEC aptasensor for diclofenac (DCF). It was observed that GR-CdS modified electrode exhibited a high and stable photocurrent upon visible light illumination, due to the excellent electrical and optical property of GR as well as the high absorption efficiency of CdS in the visible region. While Au NPs were added to GR-CdS/FTO, a further enhancement in photocurrent response was observed owing to surface plasmon resonance. Moreover, the Au NPs were advantageous to immobilize the SH-terminated aptamer used as a biorecognition element to DCF. Upon interaction of DCF with the immobilized aptamer, the DCF molecules were captured by the aptasensor. When the sensor was illuminated with visible light, an enhanced PEC current response was observed due to the oxidation of the captured DCF by the photogenerated holes. Under the optimized conditions, the sensor showed a PEC response to DCF in the linear range of 1 to 150 nM, with a detection limit of 0.78 nM. Thus, a highly selective and sensitive PEC sensor for the determination of DCF was provided.

V.P2.9
18:00
Authors : Bin Wang, Jingdong Zhang*
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, P.R. China

Resume : Electrochemical sensors based on hemin-graphene nanocomposites (H-GNs) and molecularly imprinted polymer are developed for sensitive and selective detection of 4-aminophenol (4-AMP). The 4-AMP molecularly imprinted polymer was prepared successfully by using methacrylic acid (MAA) as functional monomer and ethylene glycol dimethaerylate (EGDMA) as crosslinker. The MIP was characterized by infrared spectroscopy and scanning electron microscopy. H-GNs were synthesized through the π-π interactions. H-GNs, serving as the loading platform for MIP immobilization, have intrinsic peroxidase-like activity, which can catalyze the reaction of 4-AMP. As an electrochemical sensor, the MIP/H-GNs/GCE exhibited strong catalytic activity toward the reduction of 4-AMP which was demonstrated by cyclic voltammetry (CV). Under optimized conditions, the sensor showed a linear response to the concentration of 4-AMP in a range from 0.3 to 25 μmol•L−1 (R2=0.997)with a detection limit (3S/N) of 0.06 μmol•L−1. Moreover, the imprinted sensor exhibited excellent specific recognition ability to 4-AMP which could avoid the interference of other structurally similar phenolic compounds. The proposed electrochemical method was successfully applied to produce a sensor for the detection of 4-AMP in real water samples.

V.P2.10
18:00
Authors : Hualing Liao, Qijin Wan, Yi Liu
Affiliations : School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430073, China E-mail: qijinwan@wit.edu.cn

Resume : An interface was fabricated using carbon nanotubes (CNTs) as the catalyst support and palladium nanoparticles (Pd) as the electrocatalysts. The Pd/CNT nanocomposite was synthesized with ethylene glycol reduction method. Such a nanocomposite based interface was characterized using transmission electron microscope, energy dispersive X-ray spectroscopy, x-ray diffraction, voltammetry, and impedance. On the Pd/CNT coated electrode, the electrocatalytic oxidations of those liquid fuels (e.g., alcohols, carboxylic acids and aldehydes) occur similarly in two steps: the oxidations of freshly chemisorbed species in the forward (positive-potential) scan, and then in the reverse scan (negative-potential) the oxidations of the incompletely oxidized carbonaceous species formed during the forward scan. The oxidation charges are adopted for the first time to study their oxidation mechanisms and oxidation efficiencies. The oxidation efficiency follows the order of aldehyde (formaldehyde) > carboxylic acid (formic acid) > alcohols (ethanol > methanol > glycol > propanol). Such a Pd/CNT coated electrode is thus promising to be applied as the anode for the facilitation of direct fuel cells.

V.P2.11
18:00
Authors : Fen Yu, Lina Zhu, Qijin Wan,*
Affiliations : School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, Wuhan 430073, China E-mail: qijinwan@wit.edu.cn

Resume : A bucky-gel based electrode, composed of dithizone, ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate), and multi-walled carbon nanotubes (MWCNTs), was fabricated. After its optimization, this electrode was characterized using scanning electron microscope, voltammetry, electrochemical impedance spectroscopy, and chronoamperometry. On a bucky-gel coated glassy carbon electrode, femtomolar (fM) leveled lead ions were electrochemically detected using differential pulse anodic stripping voltammetry. After the accumulation of lead ions into the bucky-gel modified electrode at −1.2 V vs. saturated calomel electrode for 5 min in a pH 4.4 sodium acetate–acetate acid buffer solution, an anodic wave at −0.58 V is noticed. The anodic peak current is detectable for lead ions in the concentration range from 1.0 μM down to 500 fM. The detection limit is calculated to be 100 fM. The proposed method was successfully applied for the detection of lead ions in lake water.

V.P2.12
18:00
Authors : Wenshuai Hu, Xiaoyu Zhao*, Shue Qiu, Zuoliang Sha, Juankun Zhang*
Affiliations : College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology

Resume : Nowadays, graphene/reduced graphene oxide has attracted more concerns because of its superior mechanical strength, low density and high heat conductance. The various applications have been developed on its mechanical, electrical and chemical properties. The property of graphene with larger surface area and better conductivity makes molecular imprinting electro-polymerization monomer to produce polymeric membrane with more effective imprinted sites, greater adsorption capacity and adsorption efficiency. Graphene and its composites is suitable for modifying electrochemical biosensors. In the last few decades, various papers have been reported about chemical, optical, adsorption and electronic properties of nanostructured materials. Especially AuNPs are used frequently as electrode surface in the fabrication of sensors/biosensors. In addition, the nano-sized AuNPs can enhance the electrode conductivity, the rate of electron transfer and the analytical sensitivity. Therefore, nano-sized AuNPs and its composites is suitable for building electrochemical biosensors. Erythrosine(ERT,C20H6I4Na2O5), as a synthetic pigment, often used in fruit flavor drinks, cakes, candy, dispensing wine, carbonated drinks and other foods. Because of their bright colors, good dyeing force, the price is cheap, widely used in food processing. But studies have shown that almost all of the synthetic pigments cannot provide nutrients to the human body, some synthetic pigment even endanger human body health for its carcinogenicity. Erythrosine belongs to a synthetic pigment and is a kind of widely used in food industry of colorants, due to the dangers of excessive edible has the potential to human body health, the daily intake of erythrosine are restricted. In view of the widespread existence of ERT and its harmfulness, to establish an efficient, fast, accurate, simple and economical method to detect ERT is very necessary. Molecularly imprinted polymers shows selective recognition of specific molecules caused by the covalent or non covalent interactions between the template molecules and functional monomers. It possesses the ability to selectively identify target molecules, and have the advantages of anti-acid and alkali resistance, good atability, easy preparation and so on. In this paper, a high sensitivity and quantitative detection of ERT molecularly imprinted membrane sensor was successfully constructed based on the electro-polymerization technology and a sensitive imprinted electrochemical sensor based on gold nanoparticles(AuNPs) in 2-aminoethanethiol(2-AET) functionalized graphene oxide(GO) modified glassy carbon(GC) electrode was fabricated for fast and direct determination of erythrosine.

V.P2.13
18:00
Authors : Damian ?ukawski, Filip Lisiecki, Alina Dudkowiak
Affiliations : Damian ?ukawski, Alina Dudkowiak, Faculty of Technical Physics, Poznan University of Technology, Poland; Filip Lisiecki, Institute of Molecular Physics, Polish Academy of Sciences, Poland

Resume : The ocean oil spills are one of the largest environmental threats caused by human activity. Therefore, it is the matter of highest importance to find efficient ways of removing oil from ocean's water table. The recent progress in nanotechnology showed that properly engineered carbon nanomaterials are superhydrophobic and may act as selective oil sorbents [1,2]?. Moreover, their low cost makes using them feasible in industrial applications. In this research we propose coating cellulosic materials by graphene flakes by simple dip coating method. The obtained cellulose/graphene filter is highly hydrophobic and simultaneously strongly absorbs oils and organic solvents. Additionally, it was proofed that the procedure is applicable for various cellulosic materials, showing different purity and porosity. It was shown that absorption selectivity exceeds 90% for each cellulosic material and reaches 99% for the best samples. Moreover, different carbon nanomaterials, such as carbon nanotubes and carbon black, also gave promising results. References [1] Gupta, S.; Tai, N.-H. J. Mater. Chem. A 2016, 4 (5), 1550?1565. [2] Ge, B.; Zhang, Z.; Zhu, X.; Men, X.; Zhou, X.; Xue, Q. Compos. Sci. Technol. 2014, 102, 100?105.

V.P2.15
18:00
Authors : Andrius Sakavicius, Algimantas Luksa, Gvidas Astromskas, Viktorija Nargeliene, Virginijus Bukauskas, Arunas Setkus
Affiliations : State research institute Center for Physical Sciences and Technology, Department of Physical Technologies, Saulėtekio ave. 3, LT-10257 Vilnius, Lithuania

Resume : We investigate the influence of annealing to Metal/Graphene contacts. CVD grown graphene is transferred on already patterned CTLM metal (Nickel and Gold) contacts. ‘’Top transfer’’ strategy directly allows to investigate the topography of graphene surface and to measure electrical properties of graphene layer induced by metal contacts. Raman spectroscopy, Kelvin Probe Force Microscopy (KPFM) and optical sample observation were used to associate surface morphology to surface electrical properties and modifications induced by thermal anneal. The stress and doping effects of graphene layer could be interpreted referring to Raman and KPFM spectroscopies. Defects or contamination observed in optical images of sample could be easily identified at Raman spectroscopy mapping and KPFM images. We conclude that two main mechanisms of Metal/Graphene contacts occur during anneal process. These both mechanisms improve electrical interaction of Metal/Graphene structure. The first mechanism is effected by physical or chemical adsorption of graphene layer to metal contacts. This process most dominant within a few minutes of anneal time. By increasing anneal time we observe the second process – graphene layer doping by metal contacts. Strain effects occur at graphene layer in contact to metal surface. Furthermore, combination of KPFM mapping and Raman spectroscopy mapping gives essential information about graphene transferred on the top of contacts.

V.P2.16
18:00
Authors : André F. Sartori (1), Heleen Payens (1), Marco Girolami (2), Alessandro Bellucci (2), Daniele M. Trucchi (2), Thijs Boehme (3)(4), Thomas Hantschel (3), Wilfried Vandervorst (3)(4), Josephus G. Buijnsters (1)
Affiliations : (1) Department of Precision and Microsystems Engineering, Research Group of Micro and Nano Engineering, Delft University of Technology, Delft, The Netherlands; (2) CNR-ISM ? Rome, Italy; (3) Imec, Leuven, Belgium; (4) KU Leuven, Department of Physics and Astronomy, Leuven, Belgium

Resume : In this work, we will address the utilisation of novel micro/nano structures created by top-down approaches on the surface of highly conductive boron-doped diamond films for the enhancement of electrochemical detection in aqueous media. Boron-doped diamond (BDD) films have been used since many years as electrodes in environments that require high electrode stability, robustness and reproducibility. More recently, diamond has been applied as (micro)electrodes for (bio)electrochemical sensing, due to its large potential window, low background current and inherent biocompatibility. Typically, as-grown BDD films are used for such purposes. A few reports on nanostructured BDD films have already demonstrated substantial performance gains in electrochemical sensing. However, structuring all-diamond electrode surfaces involves complex cleanroom processing (e.g. lithography, reactive ion etching) that are costly and time-consuming, and therefore new fabrication routes are desirable. Here, we will describe novel, simple and straightforward fabrication techniques for diamond surface structuring. The electrochemical sensing performance of the fabricated BDD electrodes will be evaluated with standard, typically employed redox couples, and contrasted with as-grown electrodes. Finally, novel application towards glucose sensing will be explored. The electrochemical characterisation will be done by cyclic voltammetry and electrochemical impedance spectroscopy.

V.P2.17
18:00
Authors : Haihua Wu 1,2; Liwen Sang 1; Tokuyuki Teraji1; Tiefu Li3; Kongping Wu1; Masataka Imura1; Jianqiang You2; Yasuo Koide1; Meiyong Liao1*
Affiliations : 1 National Institute for Materials Science, Namiki 1-1, Tsukuba,305-0044Ibaraki,Japan ; 2 Beijing Computational Science Research Center, Beijing, 100193 China; 3 Institute of Microelectronics, Tsinghua University, Beijing 100084, China

Resume : Hybrid systems combined diamond NEMS cantilevers with electrochemical techniques provide a promising scheme for high-resolution electrochemical sensors with wide potential window and excellent chemical inertness. The authors report on the marked improvement of the quality factor (Q-factor) of single crystal diamond (SCD) nanoelectromechanical system (NEMS) resonators through annealing in oxygen ambient. The SCD NEMS resonators were fabricated by ion implantation assisted technique. The resonance frequency followed well the inverse power law relationship with the length of the cantilevers despite of the annealing. It was observed that there was little modification in the resonance frequency and Q-factor at 430 oC, while an obvious red-shift in the resonance frequency occurred at 500 oC. Meanwhile, a marked improvement in the Q-factor from around 3500 to 7000 was observed at 500 oC. The frequency red shift is due to the etching of diamond with a rate of 0.4-0.5 nm/hour at 500 oC. The analysis of the energy dissipation discloses that the surface effect dominates the energy loss mechanism for the SCD NEMS resonator. The improvement of the Q-factor is thus attributed to the elimination of the surface defects. The SCD NEMS resonators provide a sensitive scheme to function as electrochemical sensors or to examine the interface interactions between reactants during the electrochemical process.

V.P2.18
18:00
Authors : Cheng-Zhang Yang, Xin Zhang, Yan-Jun Hu
Affiliations : Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China

Resume : Tremendous research efforts have been dedicated to fabricating high quality Zn-doped CdTe quantum dots for any potential biomedical applications. In particular, the correlation of issues regarding how QDs interact with DNA is of greatest importance. Herein, a pH-responsive study of the interactions between CdTe:Zn2+ quantum dots with four different sizes and calf thymus DNA (ctDNA) was conducted using multispectroscopic techniques and electrochemical investigation. Fluorescence studies revealed that this interaction process is predominantly a static processs and groove binding was the main binding mode for CdTe:Zn2+ QDs to DNA, the thermodynamic parameters ΔG, ΔH, and ΔS with temperatures changes indicated that the hydrogen bonds and van der Waals interactions played major roles in the reaction. Furthermore, CD spectroscopy analysis indicates that the normal conformation of DNA is discombobulated by CdTe:Zn2+ QDs. In addition, the electrochemical behaviour of the affinity of CdTe:Zn2+ QDs for DNA agreed well with the results obtained from fluorescence experiments. This study might be meaningful for understanding of the molecular binding mechanism of QDs for DNA and provides a basis for QDs labeled systems.

V.P2.19
18:00
Authors : Chun-Yan Liang, Wei Xia, Yan-Jun Hu
Affiliations : Hubei Key Laboratory of Pollutant Analysis & Reuse Technology, Department of Chemistry, Hubei Normal University, Huangshi 435002, PR China

Resume : Carbon dots (CDs) are a star of carbon nanomaterials because of their superiority in water solubility, chemical inerness, low toxicity, ease of functionalization and resistance to photobleaching. Carbon dots have been widely applied in bioimaging and nanomedicine. In this study, bovine serum albumin (BSA) was chosen as a template protein to explore the interaction between serum proteins and CDs. Our group selected a bottom-up synthetic route, One-pot green synthesis CDs by used ascorbic acid as carbon precursor water phase reflow at 90℃ under strirring for 2.5h, and the CDs of we synthesis emit colour is different between that many people used ascorbic acid as carbon precursor. UVvis absorbance, fluorescence spectroscopy, and electrochemical approaches ect will be choose to explore interaction between the CDs and BSA.

V.P2.20
18:00
Authors : Rui Hao, Hua Wang* and Lin Guo
Affiliations : School of Chemistry, Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, Beihang University, Beijing 100191, P.R. China E-mail: wanghua8651@buaa.edu.cn

Resume : Currently, renewable and low-cost electrode materials are being intensively pursued to meet the development of sustainable electrochemical energy-storage systems. Chitin, which is the second most abundant biopolymer throughout the natural world derived from the exoskeletons of arthropods and shells of cephalopods, owns many attractive properties such as renewability, nontoxicity, intrinsically fibrous structure and high content of nitrogen. Herein, the nitrogen-doped amorphous carbon nanofibers (NACF) fabricated by directly pyrolysis of chitin is used as anode material in potassium ion batteries (KIBs) for the first time. The NACF electrode delivers excellent performance, such as high capacity, high rate capability, and stable long cycling life. The superior electrochemical performances are mainly attributed to synergistic effect of the unique one-dimensional porous nanofibers benefiting the transmission of electron/electrolyte, and the N-doped amorphous nanostructure increasing electrical conductivity and active sites. Our work provide a new approach for the preparation of heteroatom-doped carbonaceous materials with unique porous nanofibers microstructure using natural enlightenment, which should inspire us to explore more other advanced materials with value-added attributes by treatment of renewable bio-waste.

V.P2.21
18:00
Authors : Zijun Shi, Yanfang Gao*
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051, People?s Republic of China

Resume : Enormous research efforts have been contribute to the design and fabrication of exceptional structure with higher complexity, hoping to develop supercapacitors in order to meet the growing demands for both high power density and energy density. Herein, we have designed and fabricated a hierarchical structure of a Co3O4@ biomass-derived carbon fiber @Co3O4 (@BCF@) consisting of hollow porous carbon fiber as the sandwich layer and Co3O4 particles both as an internal shell and an external cladding layer. When @BCF@ are used for supercapacitors, possesses excellent electrochemical performances, such as high specific capacitances (892 F g?1 at a current density of 0.5 A g?1) and long-term cycling stability (retained 88% even after 6000 cycles). Meanwhile, it also exhibits the potential application value in asymmetric supercapacitors. The selected biomass-sandwich carbon fiber with porous structure not only can provide ideal ?electron superhighway? to surmount the blemish of the high resistance in great majority of the oxide electrodes, but also serve as the available backbone of inner wall space, which could load more Co3O4 particles per unit electrode area to maximize redox reaction. This eximious biomass-sandwich structure provides an electrode candidate that is promising for the development of energy storage devices in the near future.

V.P2.22
18:00
Authors : Xiaohui Liu, Yanfang Gao*
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology, Hohhot, 010051, P.R. China

Resume : Innovative energy storage technology lies at the heart of the advances that have already been made in energy conversion and storage devices, for example the introduction of supercapacitors. They can operate at high charge and discharge rates over an almost unlimited number of cycles and realize energy recovery, and therefore are gaining increasing popularity in high power energy storage applications. Specifically research and industrial developments for supercapacitors are essentially oriented to improving the device?s energy density through the design of novel electrode concepts. Herein, nickel foam as an ideal electrode architecture, which consists of a 3D interconnected network of electronic transmission. More interesting, uniform nano carbon particles (~20 nm) will be generated and can be well distributed on the surface of nickel substrate in a candle flame. The synthesized carbon particles consisted of a unique structure of 3D chain-like interconnected struts with highly wrinkled surfaces. Unlike other fabrication methods of supercapacitor electrodes, the processing described in this work is fast and straightforward, with no toxicity. Electrochemical measurements indicated that the flame-spray processing of supercapacitors obtained a high electric double layer capacitance (236.8 F g-1 at 0.3 A g-1) and excellent cycling stability (only 3% loss was observed after 10000 cycles at 5 A g-1), which are much higher than the electrodes fabricated by a traditional binder-bearing technique.

V.P2.23
18:00
Authors : Junbo Chang, Xin Chen*, Qiang Ke
Affiliations : The Center of New Energy Materials and Technology, College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, China

Resume : Fullerene can be potentially used as the electrocatalyst for oxygen reduction reaction (ORR) due to its curvature and pentagon defect. In this study, the ORR mechanisms and catalytic abilities of pure and N-doped fullerenes were investigated via DFT computations. Four different sized fullerenes, C20, C40, C60, and C180, with respectively the diameter of approximately 0.4, 0.6, 0.7, and 1.2 nm, were utilized to investigate the size effect on the ORR performance. The results reveal that the smallest (C20 and N-doped one) and the largest (C180 and C179N) fullerenes are not effective ORR catalysts candidates due to their unsuitable adsorption strength to the ORR species. In contrast, N-doped C40 and C60, with the adsorption energy much close to those on Pt(111), manifest high ORR activity potentials. Further analysis of the relative energy diagram shows that the ORR process on C19N and C179N is completed through a H2OO dissociation mechanism, while on C39N and C59N it will undergo an OOH dissociation pathway. In addition, the C39N has the largest decreased energy of rate-determining step in the relative energy profile, suggesting its ORR activity is the best among all the different sizes of fullerenes we studied.

V.P2.24
18:00
Authors : Yanying Wang, Xiaoxue Ye, Chunya Li ∗
Affiliations : College of Chemistry and Materials Science, South–Central University for Nationalities, Wuhan 430074, China

Resume : 1-[3-(N-Pyrrolyl) propyl]-3-butylimidazolium bromide ionic liquid was synthesized, and was used as a modifier to functionalize graphene oxide nano-sheets through the interaction between the carboxyl anion and imidazolium cation to produce a graphene oxide-ionic liquid nanocomposite. The obtained graphene oxide-ionic liquid nanocomposite was drop coated onto a glassy carbon electrode surface, and then cyclic votammetric scanning was performed to polymerize ionic liquid to fabricate a graphene oxide/poly ionic liquid nanocomposite film modified electrode. X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy and electrochemical impedance spectroscopy were used to characterize the obtained graphene oxide-ionic liquid nanosheets and the nanocomposite film modified electrode. Electrochemical behavior of bisphenol A at the film modified electrode was investigated, and the experimental conditions for the determination of bisphenol A were optimized. An irreversible oxidation peak was observed for bisphenol A at the nanocomposite film modified electrode. Compared with bare glassy carbon electrode, the oxidation peak current of bisphenol A at the nanocomposite film modified electrode was significantly increased. A good linear relationship between the oxidation peak current and the bisphenol A concentration was found in the range of 2.0 × 10-7 ~ 1.0 × 10-5 mol L-1, the detection limit was 1.7 × 10-8 mol L-1. The method was successfully used for the determination of bisphenol A in plastic drinking bottle, and the results were consist with these obtained by high performance liquid chromatography.

V.P2.25
18:00
Authors : Guoqiang Wang, Hongyang Ke, Yu Wang, Meichuan Liu, Guohua Zhao
Affiliations : School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, China

Resume : It is of great significance to develop efficient monitoring strategies with high sensitivity and selectivity for MC-LR, one of the most highly concerned typical microcystic toxins in water samples. A convenient signal-on electrochemical aptasensor for E2 was proposed based on graphene controlled assembly and DNase I enzyme cleavage-assisted target recycling amplification strategy, as well as Au nanoparticles’ synergistic effect. Highly sensitive detection of MC-LR was achieved with a linear range from 1.0 to 100.0 pM and the detection limit of 0.8 pM, attributed to the double signal recycling amplification functions. Besides, this method also exhibited high selectivity while being used to detect 100-fold concentration other six potential coexisting interferents containing N and P, such as omethoate, glyphosate, paraquat, trichlorfon, acetamiprid and monosultap. Real water sample analysis showed its reliability and potential in practical environmental monitor. A promising electrochemical aptasensor platform towards MC-LR with high selectivity and sensitivity has thus been provided. (Acknowledgements: National Natural Science Foundations of China (NSFC) (No. 21377092), and the Fundamental Research Funds for the Central Universities.)

V.P2.26
18:00
Authors : Yu Wang, Meichuan Liu*, Guohua Zhao
Affiliations : School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, Siping Road 1239, Shanghai 200092, China

Resume : The worldwide use of atrazine, a kind of the most widely used triazine herbicides, had caused a great influence on the environmental and human health because of its potential disrupter of cell chromosome structure, estrogens metabolism and immune systems. Traditional detection methods of atrazine usually suffer from limitations of slow speed, complex analysis process, high cost, and not applicable for field monitoring, etc. It is of great significance to develop a convenient and on-site capable detection method towards atrazine. Self-powered sensors had attracted great attention in the past decade due to their capacity of harvesting energy from the environment and had no requirement for external electrical power supply during the chemical sensing of analytes. It is particularly outstanding in great potential for its feasible in on-site monitoring, which is highly demanded for the environmental monitoring issues. So far, most of the sensor were based on biofuel cell (BFC) or microbial fuel cell (MFC), which had been applied in medicine and biological analysis. While the self-powered sensors have seldom been applied in environmental analysis because of the much severe and complexed condition of the samples, which might be advertised to the performance of the BFC or MFC, as well as the potential demands in high acidic or basic environment. At the same time, low output signal, insufficient stability in a complex environment due to the enzyme deactivation, and poor in selectivity towards special targets of most of the self-powered sensors are the also their main obstacles. In the present work, we developed a self-powered aptasensor system to detect environmental pollutant atrazine with high selectivity based on a kind of very simple glucose biofuel cell as anode and an aptamer-loading electrode as cathode. By virtue of using carboxylated multi-walled carbon nanotubes (MWCNTs) as the functional bridge for the anode substrate electrode and the biomolecule glucose dehydrogenase, stable and strong output power density signal can be obtained with nicotinamide adenine dinucleotide (NAD +/NADH) used as a cofactor. The carboxylated multi-walled carbon nanotubes (COOH-CNTs) not only played a key role in linking bio- enzyme molecule to substrate electrode, but also improved the effciency of electron transfer due to its good conductivity. Meanwhile, anti-atrazine aptamer was loaded to gold electrode to serve as the recognition elements to atrazine. When atrazine was combined with aptamer specifically, the formation of its steric hindrance and electrostatic repulsion can blocked the electron transfer efficiency in cathode surface, thus resulted a remarkable decrease of biofuel cell in output power density. Based on this principle, the constructed sensor has been successfully proposed to detect atrazine with high selectivity. A detection limit of 10 nM was reached. A simple, fast, efficient, low-cost, and especially self-powered sensing platform to atrazine has been provided, with no need of an external power supply. It opens promising prospects of self-powered aptasensor to the practical application in the environmental water pollution treatment and monitoring.

V.P2.27
18:00
Authors : Jing Yu, Yu Wang, Meichuan Liu, Guohua Zhao
Affiliations : School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, China

Resume : Microcystin-LR is a widespread and toxic contaminant produced by the freshwater Cyanobacteria. It is an electrochemical inert species which is difficult to be directly detected by a simple electrochemical method. In this study, a highly sensitive and selective photoelectrochemical (PEC) sensor which utilize a graphene-based vertically aligned TiO2 nanotubes (TiO2 NTs) as photoelectrochemical functional interface, and surface molecularly imprinted polymer (MIP) modification as recognition element. The constructed PEC sensor exhibits outstanding performance in MC-LR detection with a linear range from 0.01 to 50 nmol L-1 and a limit of detection of 0.01 nmol L-1.The PEC sensor also presents excellent selectivity while coexist other organic contaminants including monosultap, glyphosate, acetamiprid, omethoate, gramoxone and dipterex with a 100 times concentration than MC-LR. The relative photocurrent of them are all less than 15%. The favorable detection sensitivity is mainly attributed to great conductivity and the giant π-π conjugated structure of graphene, which is great helpful to improve the separation of electron-holes on TiO2 NTs, yielding its enhanced photoelectric activity. The good selectivity of the PEC sensor is resulted from the specific action from the surface MIP layer. A simple and promising PEC sensor towards MC-LR detection has therefore been provided with the potential application capacity in real water samples.

V.P2.28
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09:00 Plenary Session - Main Hall    
12:30 Lunch break    
 
Energy and Catalysts : Wei Chen
14:00
Authors : Paula E. Colavita, Carlota Domínguez, James A. Behan, Serban N. Stamatin, Md. Khairul Hoque, Roman Ivanov, Irina Hussainova
Affiliations : 1. School of Chemistry, Centre for Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN) and AMBER Research Centre, Trinity College Dublin, College Green, Dublin 2, Ireland 2. Tallinn University of Technology, Ehitajate 5, 19180 Tallinn, Estonia

Resume : Effective control of interfacial properties of carbon electrode materials is often critical to achieve their desired performance in applications ranging from electrocatalysis to capacitive storage. Modification of morphology and chemical composition offer versatile routes for tailoring the electrochemical response of these materials. Nitrogen incorporation is of particular interest, as it has been shown to result in increased activity in the oxygen reduction reaction (ORR), a critical reaction in fuel-cell technologies. However, the origin of this activity is not well understood and rational optimization of ORR activity remains challenging due to the interplay among electronic, surface and morphology changes associated to the introduction of N-sites. We report on synthetic strategies for investigating the effect of morphological and chemical changes in carbon materials. First, chemical vapour deposition was used to create graphene-like nanostructured carbon with tailored edge and defect density. A combination of microscopy, spectroscopy and electrochemical methods was used to correlate carbon chemistry and morphology to ORR activity. Second, the effect of nitrogenation was investigated using smooth carbon film electrodes prepared via sputter deposition. A combination of optical and electrochemical methods reveals that low-levels of nitrogenation result in fast electron transfer kinetics compared to non-nitrogenated carbons. Surface effects however can also play an important role in the case of selected redox species due to their interactions with N-sites. Finally, we discuss results on thin film electrodes with homogeneous N-site chemistry as model materials to test the role of N-site chemistry in ORR.

V.11.1
 
Energy I : Hua Zhang
14:30
Authors : Zhenyu Zhang, Bin Liu, Wenjun Zhang*
Affiliations : Center of Super-Diamond and Advanced Films (COSDAF), and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong SAR, PRC

Resume : The structure design of an electrode is one of the most important factors affecting its reaction kinetics, the capability of mass transportation with electrolyte, and consequently the performance of an electrochemical energy storage or conversion system. A successful approach that has been widely demonstrated is to construct a three-dimensional (3D) nanoscale-structured electrode, which enables enhanced ion and electron transport, increased active material loading, and improved mechanical stability. Ascribing to their combined superior inherent properties and the special structure configuration, 3D graphene and transition metal dichalcogenide (TMD) nanostructures have demonstrated promising applications in electrochemical energy conversion and storage. In this presentation, we report our recent progress in applying 3D graphene, TMD and related composites in the electrochemical electrode applications derived from their distinct merits of structure and properties, e.g., supercapacitor, lithium ion battery, vanadium redox flow battery, and fuel cell.

V.2.1
15:00
Authors : K. M. Skupov, I. I. Ponomarev, D. Y. Razorenov, Iv. I. Ponomarev, Y. A. Volkova, V. G. Zhigalina, O. M. Zhigalina, Y. M. Volfkovich, V. E. Sosenkin, S. S. Bukalov, A. V. Sivak
Affiliations : K. M. Skupov, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; I. I. Ponomarev, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; D. Y. Razorenov, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; Iv. I. Ponomarev, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; Y. A. Volkova, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; S. S. Bukalov, Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Vavilova St. 28, Moscow, 119991, Russia; O. M. Zhigalina, Shubnikov Institute of Crystallography of Federal Scientific Research Centre ?Crystallography and Photonics? of Russian Academy of Sciences, Leninsky Av. 59, Moscow, 119333, Russia; V. G. Zhigalina, Shubnikov Institute of Crystallography of Federal Scientific Research Centre ?Crystallography and Photonics? of Russian Academy of Sciences, Leninsky Av. 59, Moscow, 119333, Russia and National Research Center ?Kurchatov Institute?, Akademika Kurchatova Sq.1, Moscow, 123182, Russia; Y. M. Volfkovich, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Science, Leninsky Av. 31, Moscow 119071, Russia; V. E. Sosenkin, Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Science, Leninsky Av. 31, Moscow 119071, Russia; A. V. Sivak, Inenergy LLC, 2nd Kotlyakovsky Lane. 18, Moscow, 115201, Russia.

Resume : Development of high temperature polymer electrolyte membrane fuel cells (HT-PEMFC) on polybenzimidazole membrane is highly important for alternative energy because it allows to use hydrogen contaminated with CO. Advances in hydrogen-air HT-PEMFC are related with the increase in durability of membrane-electrode assembly. In order to improve the traditional scheme of electrode producing, carbon black support for the electrocatalyst (Pt, Ni, etc) may be changed by more stable carbon nanostructures. For the first time, we have shown that carbon nanofiber paper, which was obtained by the electrospinning of polymer (such as polyacrylonitrile or polyheteroarylenes) solution with further pyrolysis of self-supporting mats, is suitable for Pt deposition and gas-diffusion electrode producing for HT-PEMFC. Also, we have prepared a composite nanofiber electrode when Zr and Ni salts are added to the polymer electrospinning solution. After pyrolysis (900-1200 oC), Ni(0) and ZrOx particles are incorpotated into carbon nanofibers. As shown, it facilitates Pt deposition which proceeds on Ni(0) nanoparticles. For the new carbon composite electrode, polarization curve characteristics are improved compared to non-composite ones. Polarization curve values reached 0.702 V at 0.2 ?/cm2 and 0.570 V at 0.6 ?/cm2 at 180 oC which is comparable with Celtec® P1000. New carbon materials were characterized by SEM, TEM, EIS, CV, Raman spectroscopy, XPS, standard contact porosimetry, elemental analysis.

V.11.3
15:15
Authors : Yoshitaka Saito, Minoru Ashizawa, Hidetoshi Matsumoto
Affiliations : Department of Materials Science and Engineering, Tokyo Institute of Technology

Resume : Design of carbon electrodes with large ion accessible surface area and low ion transport resistance is required to achieve high energy- and power-density supercapacitors. Graphene is an attractive material for the supercapacitor electrode due to its large surface area and high electrical conductivity. However, most of graphene electrodes have highly ordered structure where graphene sheets parallel arranged to electrode film, which prevented the ion transport during charge-discharge process. Recently, it is reported that the prevention of restacking in chemically-reduced graphene sheets enable forming the narrow gap between graphene sheets suitable for ion transport [1]. Herein, we try to from disorderly-assembled graphene nanoribbon (GNR) electrode to achieve low ion transport resistance by using pseudo one-dimensional (1-D) GNR instead of 2-D graphene, because 1-D nanocarbon is easy to form the network structure. In the present study, graphene oxide nanoribbon were reduction by hydrazine treatment and GNR films were prepared by filtration directly from the reduced GNR dispersions. During the filtration, the reduced GNRs assembled into a film structure. Our X-ray diffraction analyses demonstrate that the restacking between the reduced GNRs does not occur in the obtained GNR films, indicating that the GNR films has disorderly assembled structure. The GNR-film-based supercapacitor shows high capacitance of 225 F/g at a current density of 0.1 A/g, with superior retention of 71 % even at a high current density of 100 A/g. Disorderly-assembled GNR electrode offers new possibilities of high energy- and power- density supercapacitor with low ion transport resistance. [1] Yang, X. et al. Adv. Mater. 23, 2833 (2011).

V.11.4
15:30 Coffee break    
 
Early Researcher Session : Nianjun Yang
16:00
Authors : Zijun Shi, Yanfang Gao,*
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology, Hohhot 010051, People’s Republic of China

Resume : Reduced graphene oxide (RGO) own outstanding physicochemical properties arising from itself structure, having vast active defect sites and functional groups on RGO sheet, exhibiting great potential for practical application. Nevertheless, the aforementioned structure increased the resistance and the effects of van der Waals force during the reduction process. Consequently, in this work, through rapidly, low-cost and reliable candle soot-derived carbon nanoparticles (CNPs) method, using uniform microscale CNPs (~20 nm) serving as template embed into the layers of RGO to construct 3D RGO. CNPs possess a large surface area to promote molecular adsorption at the interface, which could ensure high efficiency during the electrochemical process. This construction resolved the issues of impedance and π-π stacking, moreover, presented remarkable electrochemical performance. Electrochemical capacitive performance of 3D RGO enhanced to 312 F g-1 at a current density of 0.5 A g-1, also demonstrated a long-term cyclic stability (maintained 94.2% capacity even after 10000 cycles). In addition, as a symmetric electrode, 3D RGO has excellent structural advantage, when the operating voltage increased to 1.6V, a further high-level energy density of over 42.3 Wh kg -1 at a large power density of 1280 W kg -1 can be obtained.

V.12.1
16:15
Authors : Ella Bentin, Jovana Vukajlovic, and John S. Foord
Affiliations : University of Oxford; Diamond Science and Technology CDT University of Warwick

Resume : Voltammetric behaviour of the genotoxic pollutant 2-amino-9-fluorenone was investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and square wave voltammetry (SWV), in both anodic and cathodic potential regions. Previous work with 2-AFN using a variety of electrode materials had been affected by the extensive fouling, and only periodic mechanical regeneration of the electrode surface achieved repeatability. Boron-doped diamond (BDD) has higher resistance to fouling by analyte media than other electrode materials, we found that 20 pulses of alternating +/10 mA cm2 with 100 ms duration successfully regenerated the BDD surface and produced repeatable currents. The interaction between 2-AFN and guanosine and adenosine, single-stranded DNA, and double stranded DNA were examined at the bare BDD electrode. Additionally, performance of oxygen-terminated BDD decorated with DNA were investigated after exposure to various concentrations of 2-AFN, to characterise the extent of the genetic damage.

V.12.2
16:30
Authors : Junxing Hao1, Liudi Ji1, Kangbing Wu1*, Chengguo Hu2
Affiliations : * Corresponding author. E-mail address: kbwu@mail.hust.edu.cn (K. Wu) 1.School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China 2.Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China

Resume : Trace and toxic elements, such as cadmium (Cd2 ) and lead (Pb2 ) pose acute or chronic risks to ecosystem because of their high stability and propagated accumulation through food chains and even threat to human life. Accordingly, exploring the sensitive, rapid and simple analytical method for precise monitoring of Cd2 and Pb2 is urgently needed. Electrochemical anodic stripping voltammetry (ASV) has been widely recognized as a promising method for determination of heavy metals owing to its low cost, good portability and specificity, on-site monitoring, high sensitivity and low limit of detection. A green method is reported to effectively and rapidly reduce graphene oxide to graphene with zinc powder at ambient. ZRGO (zinc-induced in-situ reduction of graphene oxide) was prepared by mixing graphene oxide (GO), zinc (Zn) powder, ammonium chloride (NH4Cl) in solution under stirring conditions at room temperature for 10 min. The as-prepared ZRGO was used to modify the surface of glassy carbon electrode (GCE). During this process, NH4Cl catalyzes the reduction of GO by Zn powder and causes the rapid in-situ reduction of graphene oxide obtained the freshly reduced and nanoporous graphene oxide (that is, ZRGO). The ZRGO nanomaterial were characterized by field emission scanning electronic microscope (FESEM), transmission electron microscope (TEM), atomic force microscopic (AFM), Raman, fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) to prove ZRGO has been successfully prepared. Electrochemical responses of K3[Fe(CN)6] revealed that ZRGO was capable of facilitating electron transfer and increasing surface area. The interface based on ZRGO nanomaterial exhibits a porous and three-dimensional structure, resulting in a high surface area as well as many reactive or adsorption sites for Cd2 and Pb2 . Electrochemical behaviors of Cd2 and Pb2 in water matrix were studied and the anodic stripping peak was completely separated in pH 5.0 acetate buffer solution. Compared with GCE, the ZRGO-modified GCE (ZRGO/GCE) greatly increased the anodic stripping peak currents of Cd2 and Pb2 , showing great signal enhancement effect. More importantly, the response signals of Cd2 and Pb2 on ZRGO/GCE further enhanced remarkably in the presence of Bi3 . The influences of pH value, Bi3 concentration, amount of ZRGO, accumulation potential and time on the anodic stripping peak currents of Cd2 and Pb2 were studied. Based on this sensitization effect, a novel electrochemical sensing platform with high sensitivity, fast and simultaneous detection of Cd2 and Pb2 can be constructed.

V.12.3
16:45
Authors : D. Kelly, M. M. Lounasvuori, J. S. Foord
Affiliations : Department of Chemistry, University of Oxford, Mansfield Road, OX1 3TA

Resume : Phenolic compounds are used in various industrial processes, including the preparation of petrochemicals, cosmetics and pharmaceutical products. Phenols are non-biodegradable and toxic to many organisms, and their release into the environment from the waste streams of industrial processes leads to soil and water contamination. Consequently, it is of critical importance to be able to determine levels of phenolic compounds in environmental samples. Electrochemical detection is often used for this purpose; however, the anodic detection of these compounds is complicated by electrode fouling due to electropolymerisation of phenoxy radicals. Carbon nanotubes immobilised onto glassy carbon electrodes have been reported to improve electrode performance for phenol detection; other carbon nanomaterials may therefore be expected to exhibit similar behaviour. In this study, carbon black was chosen as a cheap, readily available carbon nanomaterial to construct high surface area electrodes for use in electrochemical detection of catechol, p-nitrophenol and p-cresol. Modifying a glassy carbon electrode with carbon black is shown to improve the detection sensitivity of all three phenols as evidenced by up to 10-fold increase in oxidation current and up to 150 mV shift to lower overpotential. The reusability of a carbon black electrode in the detection of different phenolic compounds is discussed.

V.12.4
17:00
Authors : Piaopiao Wei, Kangbing Wu*
Affiliations : [Corresponding author, E-mail address:kbwu@mail.hust.edu.cn (Kangbing Wu)] School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Resume : Graphene was prepared via one-step ultrasonic exfoliation of graphite powder using N-methyl-2-pyrrolidone (NMP) as the solvent with the presence of sodium citrate. The morphology and layer structure were confirmed using SEM and TEM. Electrochemical responses of K3[Fe(CN)6] revealed that prepared graphene was capable of facilitating electron transfer and increasing surface area. On this basis, the prepared graphene was used to modify glass carbon electrode(GCE), then the electrochemical behavior of carbendazim?a kind of pesticide, was studied, and a sensitive oxidation peak was observed in pH 5.7 phosphate buffer. Compared with bare GCE, the oxidation peak current of carbendazim on graphene modified GCE is improved greatly. The influences of pH value, amount of graphene, accumulation potential and time on the oxidation peak currents of Carbendazim were studied. Based on the signal amplification of graphene nanosheets, a novel electrochemical method with high sensitivity for carbendazim was developed. The linear range was from 1.0 to 250.0 ?g L-1, and the detection limit was 0.15 ?g L-1. Finally, this new sensing system was used in lake water samples, and the accuracy was satisfactory.

V.12.5
17:15
Authors : Steffen Heuser, Zhuang Hao, Nianjun Yang, Xin Jiang
Affiliations : Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Graphene, as a zero band gap material, has opened up various promising applications for electrochemical and electronic devices. Combining graphene with silicon carbide, a semiconductor material, namely the synthesis of graphene/SiC sandwich structures or hybrid nanolaminates can then expand more electronic and electrochemical applications. In this presentation, a novel one-step technique using microwave assisted plasma chemical vapour deposition (MWCVD) will be introduced for depositing 3C-SiC/graphene hybrid nanolaminates. The characterisation of their surface morphology and chemical information with scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy will be summarized. SEM observation shows different growth types (varied thicknesses of graphene and SiC layers) at different MWCVD deposition conditions. The formation/numbers of graphene layers and 3C-SiC is further verified by Raman spectroscopy. Four-point-probe measurement was taken out to achieve information about the conductivity of the different films. Their conductivity improves with an increase of graphene amount inside the hybrid nanolaminates. With help of the transmission electron microscopy investigation, the growth mechanism, growth behaviour and the formation of the nanolaminate structure will be presented. The control of individual layer thickness of both 3C-SiC and graphene will be shown through varying the deposition parameters directly during the MWCVD process. The use of these hybrid nanolaminates for electrochemical applications, such as the capacitor electrodes for super- and pseudocondensators, will be presented in both aqueous and organic solvents.

V.12.6
17:30
Authors : Rui Hao, Hua Wang, Lin Guo
Affiliations : School of Chemistry, Beihang University

Resume : Currently, renewable and low-cost electrode materials are being intensively pursued to meet the development of sustainable electrochemical energy-storage systems. Chitin, which is the second most abundant biopolymer throughout the natural world derived from the exoskeletons of arthropods and shells of cephalopods, owns many attractive properties such as renewability, nontoxicity, intrinsically fibrous structure and high content of nitrogen. Herein, the nitrogen-doped amorphous carbon nanofibers (NACF) fabricated by directly pyrolysis of chitin is used as anode material in potassium ion batteries (KIBs) for the first time. The NACF electrode delivers excellent performance, such as high capacity, high rate capability, and stable long cycling life. The superior electrochemical performances are mainly attributed to synergistic effect of the unique one-dimensional porous nanofibers benefiting the transmission of electron/electrolyte, and the N-doped amorphous nanostructure increasing electrical conductivity and active sites. Our work provide a new approach for the preparation of heteroatom-doped carbonaceous materials with unique porous nanofibers microstructure using natural enlightenment, which should inspire us to explore more other advanced materials with value-added attributes by treatment of renewable bio-waste.

V.7.3
17:45 Closing remarks    
18:00 Best Student Presentation Awards Ceremony and Reception (Main Hall)    

No abstract for this day


Symposium organizers
Chunhai FAN Shanghai Institute of Applied Physics, CAS

Shanghai 201800 China

+86 2139194129
fchh@sinap.ac.cn
Greg M. SWAINMichigan State University

East Lansing, MI 48824-1322 USA

+1 517 3559715229
swain@chemistry.msu.edu
John S. FOORDUniversity of Oxford

OX1 3TA, UK.

+44 1865 275967
john.foord@chem.ox.ac.uk
Nianjun YANGUniversity of Siegen

Institute of Materials Engineering, Paul-Bonatz Stra. 9-11, 57076 Siegen, Germany

+49 2717402531
nianjun.yang@uni-siegen.de
Yasuaki EINAGAKeio University

Yokohama 223-8522 Japan

+81 455661704
einaga@chem.keio.ac.jp