preview all symposia

2015 Fall

Nanomaterials,Nanostructures and Nano devices


Nanocarbon Electrochemistry and Interface

This symposium will focus on electrochemical characterization and properties of diamond, CNTs, graphene, carbon particles and nanocomposites, etc. The key topics will include their application in electroanalysis, biosensing, electrocatalyst, electrosynthesis, environmental degredation, energy conversion and storage, etc.




This symposium will 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.). Electrochemical characterization of these nanocarbon materials in different media (including aqueous and non-aqueous solutions (organic and ionic liquids) and their interfacial properties will be covered. Of particular focus will be the relationships between the carbon bulk structure, electronic properties and surface chemistry their electrochemical performance (e.g. potential window, capacitance, redox activity, electrode kinetics and interactions, etc.). Applications of the nanocarbon materials in electroanalysis, electrocatalyst, electrosynthesis, environmental degradation, and energy storage and conversion will be covered. In vivo and in vitro electrochemical sensing, electrocatalytic reactions (e.g. catalyst support, metal-free catalytic reactions), organic synthesis using nanocarbon electrodes, electrochemical-photochemical degradation of environmental pollutants, supercapacitors and batteries from carbon nanomaterials are currently key topics in the field. The symposium will also include contributions on the fabrication, characterization, and application of micro and nanostructured carbon materials (e.g. micro-, ultramicro-, nano- electrode arrays, tips, etc.) and their characterization by scanning electrochemical microscopy, electrochemical AFM and spectroelectrochemistry.


Hot topics to be covered by the symposium


  • Electrochemical properties of nanocarbons and related nanocomposites
  • Simulation of carbon nanoelectrochemistry
  • Synthesis of nanocarbons for electrochemistry
  • Nanocarbon electrochemical and biochemical sensing
  • Electrosynthesis using nanocarbon electrodes
  • Electrocatalysts on nanocarbon electrodes
  • Nanocarbon electrodes for enviromental degredation
  • Nanocarbon electrodes for electrochemical energy conversion and storage
  • Electrochemistry at carbon nanostructures
  • Electrochemical functionalization of nanocarbons and their applications
  • Fabrication and applications of nanocarbon electrochemical devices


Tentative list of invited speakers


  • R. L. McCreery, University of Alberta, Canada Advanced Carbon Materials for Molecular Electrochemistry
  • K. P. Loh, National University of Singapore, Singapore Metal-Free Catalysts from Nanocarbons
  • C.E. Nebel, Fraunhofer Institute for Applied Solid State Physics (IAF), Germany Future of Diamond Electrochemistry
  • S. R. Waldvogel, University of Gutenberg-Universitat Mainz, Germany Electrochemical Organic Synthesis Using Carbon Electrodes
  • E. Brillas, Universitat de Barcelona, Spain Waste Water Treatment by Boron-Doped Diamond Electrodes
  • M. Panizza, Univeisita di Genova, Italy Degradation of Environmental Toxic Materials Using Carbon Electrodes
  • C.A. Martinez-Huitle, Campus Universitario-Lagoa Nova, Brasil Carbon Materials for Energy Storage and Conversion
  • M. Opallo, Institute of Physical Chemistry, Warsaw, Poland Electrochemistry of Nanocarbons in Ionic Liquids
  • B. A. Patel, University of Brighton, UK Bioanalytical Application of Boron Doped Diamond Electrodes
  • R. Zhou, IBM Reseach Center, USA Simulation and Experiments of Carbon Biointerface
  • Z. Liu, Soochow University, China Nanocarbons for Drug Delivery, Bioimaging and Related Applications
  • J. Li, Tsinghua University, China Energy Storage Using Nanocarbons


Tentative list of scientific committee members



  • J. Wang, University California San Diego (UCSD), USA
  • R. G. Compton, University of Oxford, Oxford, UK
  • H. Dai, Stanford University, USA
  • J.A. Garrido, Walter Schottky Institute, TUM, Germany
  • H. Kawarada, Waseda University, Japan
  • P. Mailley, Université Joseph Fourier, France
  • M.S. Strano, MIT, USA
  • S.T. Lee, Soochow University, China
  • F. Treussart, ENS Cachan, France
  • D.-W. Pang, Wuhan University, China


Start atSubject View AllNum.
09:30 Opening    
keynote : Nianjun Yang
Authors : Richard L. McCreery, Adam Bergren, Nikola Pekas, Bryan Szeto, Lucas Zeer-Wanklyn, Mitchell Semple
Affiliations : University of Alberta (U of A) and the National Institute for Nanotechnology (NINT); NINT; NINT; NINT; NINT Co-Op Student; U of A

Resume : The rapidly emerging field of Molecular Electronics investigates the behavior of organic molecules as active components in solid state electronic circuits. The focus of our research is the “molecular junction” in which a layer of molecules is oriented between two conductors, and electron transport occurs through the molecular layer. Electron transport across 1-20 nm differs fundamentally from that in standard semiconductors and thicker organic films, and often involves quantum mechanical tunneling. When molecular orbitals have suitable energies, field ionization can generate charge carriers, and transport may occur across distances much too long for tunneling. Ultraviolet photoelectron spectroscopy and photocurrent measurements from illuminated molecular junctions permit direct determination of energy levels in molecular junctions, often simultaneously with electronic conduction. Molecular junctions also produce light during current flow, indicating significant “ballistic” transport without inelastic scattering. A potential commercial application of molecular junctions in audio processing will also be described and demonstrated. (1) Yan, H.; Bergren, A. J.; McCreery, R.; Della Rocca, M. L.; Martin, P.; Lafarge, P.; Lacroix, J. C. Activationless charge transport across 4.5 to 22 nm in molecular electronic junctions, Proceedings of the National Academy of Sciences 2013, 110, 5326. (2) McCreery, R.; Yan, H.; Bergren, A. J. A Critical Perspective on Molecular Electronic Junctions: There is Plenty of Room in the Middle, Physical Chemistry Chemical Physics 2013, 15, 1065. (3) Fereiro, J. A.; Kondratenko, M.; Bergren, A. J.; McCreery, R. L.; Internal Photoemission in Molecular Junctions: Parameters for Interfacial Barrier Determinations; J. Am. Chem. Soc. 2015, 137, 1296. (4) Sayed, S. Y.; Fereiro, J. A.; Yan, H.; McCreery, R. L.; Bergren, A. J. Charge transport in molecular electronic junctions: Compression of the molecular tunnel barrier in the strong coupling regime, Proceedings of the National Academy of Sciences 2012, 109, 11498.

10:30 Coffee Break    
Carbon for Energy : Richard McCreey
Authors : Christoph E. Nebel, Wolfgang Müller-Sebert, Georgia Lewes-Malandrakis, Fang Gao
Affiliations : Fraunhofer-Institute for Applied Solid State Physics IAF, Tullastr. 72, Freiburg, Germany

Resume : Batteries are increasingly important for a variety of applications which are mobile and disconnected from power grids. Energy and power demands of devices define the design and concept of the storage devices. While lithium ion batteries have aided the portable electronics during the past two decades due to their high energy storage capability, they are too slow for devices which need energy burst. Here dielectric capacitors are the one to provide energy when peak power is required, but they are limited with respect to energy delivery. Between these two extremes supercapacitors (SCs), also called ultracapacitors or electrochemical capacitors will fill the gap in the future. They need to combine relative fast charging/de-charging cycles with respect to optimized energy supply. This is the field of surface enlarge capacitors, which show textured surfaces, lattice expanded structures or surfaces composed out of long and dense wire structures. Besides surface enlargements, the electrochemical potential window affects equally important the energy and power properties of supercaps. It is well known that diamond shows the wides electrochemical potential window of all known electrode materials. Diamond is also chemical stable and can meanwhile be deposited on large areas in nano- or poly-crystalline structures. By adding boron to the diamond lattice, diamond becomes very conductive (p-type) and is used as electrochemical electrode in a variety of applications. In this presentation we will introduce the realization of supercaps from diamond Si-based surfeces with textures. These layers are overgrown with heavily boron-doped nano-crystalline diamond films. For these experiments we used silicon-nano-wires (Si-NWs) grown by a VLS-process as substrates for the overgrowth with conducting diamond coatings. The SiNWs had typical dimensions of 10 µm length at diameters of 150 nm. Prior to overgrowth we applied a special seeding procedure using a colloidal suspension of diamond nanoparticles in water. This technique gives rise to nucleation densities in the range of 1011 cm-2. Diamond deposition was carried out in our multi-antenna plasma enhanced CVD-reactors. The standard 6 kW system with 2.45 GHz is capable of coating substrates up to 3 inch in diameter, wereas in the upscaled 915 MHz system 6 inch substrates can be coated. As boron source we used trimethyboron (TMB); the doping level was up to 5x1020 cm-3. We realized uniform diamond coatings with a thickness in the range of 200 nm. Even densely packed Si-NWs with high aspect ratio could be readily coated. Alternatively, we prepared electrodes with all-diamond nanowires by ICP etching of 10 µm thick boron-doped polycrystalline CVD diamond with Ti- or Ni nanoparticles as etching mask. The all-diamond nanowires have a much lower aspect ratio compared to overgrown Si-NWs; however the surface enhancement is up to 25 times as compared to unstructured polycrystalline films. We will summarize related physical and electrochemical properties to compare the device with standard supercaps and to discuss future applications of this new device.

Authors : Yang Liu, Zhaojun Wu, Yanfang Gao*, Jinrong Liu
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology

Resume : Supercapacitors (SCs) have attracted much more attention due to a myriad of desirable properties, including rapid charging/discharging rate, long cycle life, and the ability to deliver ultra-high power. It is noted that electrode materials play a key role in the exploiting of high performance SCs in terms of the morphology, size, porosity and so forth. In this work, biomorphic cotton fibers are pretreated under the effect of urea swelling on cellulose and subsequently used as sacrificial template to mould the hollow microtubules structure through a certain degree of calcining. During the process, cobalt nickel metal ions would be adsorbed onto the modificatory surfaces of cotton fibers and finally turned into Co-Ni oxide due to the pyrogenic decomposition and oxidation. As for the sacrificial template strategy based on liquid-solid reaction, microtubules are formed by creating at least one sheath layer around the wire-shaped template. The cotton fibers template functions as a sacrificial core which was later removed to establish the central opening through the microtubule. A detailed investigation reveals that urea could swell cellulosic biomass, not only in improving the surface chemical character of biomorphic cotton fibers, but also in facilitating the formation of multi-directional pore structure. This remarkable capacitive performance can be attributed to sufficient void space within the hollow microstructure, which effectively increases the contact area between the oxides and the electrolyte, reducing the ions diffusion pathway and buffering the volume change during cycling.

Authors : David Ávila-Brande, Daniel Arenas-Esteban, L. Carlos Otero-Díaz, Andrés Guerrero-Martínez, Gloria Tardajos, Javier Carretero-González
Affiliations : Department of Inorganic Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E–28040, Madrid, Spain. Department of Physical Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E–28040, Madrid, Spain. Polymer Ionics Research Group, Warsaw University of Technology, Warsaw, Poland

Resume : Electrical double-layer capacitors (EDLC) can store energy by electrostatic interaction between the charged surface of a porous carbon electrode and the ions present in the electrolyte. The further expansion of EDLC application for vehicles and portable electronics has directed research to increase its energy density per unit of volume. Here we present several preparation routes of nanoporous activated carbon containing a fine dispersion of nanoparticles along their microstructure. This investigation is focused on the improvement of the conductivity of the carbon electrode by insertion of noble metal nanoparticles or adding pseudocapacitance by the incorporation of less than 10 nm metal oxide nanoparticles along the surface of the electrode. As an example, after application of a Carbon-AuNps material as electrode in EDLC the volumetric capacitance value was twice (47 F cm-3) that of the activated nanoporous electrode. Moreover, the electrochemical series resistances of the supercapacitor decreased one order of magnitude after the incorporation of gold nanoparticles. Interestingly, the presence of noble metal nanoparticles also overcomes the irreversible charge storage due to the oxygen moieties typically present at the surface of the electrode. Our findings are significant because revealed an innovative preparation route for highly dense nanoporous carbon materials as well as the turn into noble-like metal of electrodes made of conventional activated nanoporous carbons.

Authors : Quan Yuan
Affiliations : College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, China

Resume : A fast growing need for renewable and sustainable energy resource has promoted the exploit of high energy storage technologies. Design and fabrication of suitable electrode material with high surface area and stability is critical for the development of electrical vehicles like supercapacitors. Porous carbon materials such as carbon nanotubes (CNTs), graphene (G) and mesoporous carbon have been used as electrode material of supercapacitors due to the high electrical conductivity, flexible structure, and superior mechanical characteristics. Carbon nanotube sponge is a three dimensional porous structure which is composed of interconnected CNTs. The intrinsic high mechanical performance of CNTs enabled the high flexibility of the whole sponge. Based on the conductive porous network, a CNT and pseudo capacity material (polypyrrole, PPy) core-shell structure were designed as flexible supercapacitor electrode. The hybrid electrode possesses the high flexibility and stability compared to PPy. Furthermore, a facile method was developed to synthesize high surface area CNT/mesoporous carbon/Platinum nanoparticles core-shell hybrid structure with high specific capacity and superior flexibility, and the application of this composite material in electrical double layer capacitor (EDLC) was further explored

12:30 Lunch Break    
Carbon for Sensing : Christoph E. Nebel
Authors : Hyacinthe Randriamahazaka, Jalal Ghilane
Affiliations : Univ. Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086 CNRS, 15 rue Jean-Antoine de Baïf, 75205 Paris Cedex 13, France

Resume : Applications regarding energy storage, biomaterials, chemical sensors, biosensors, catalysis, and photocatalysis summarize most of the fields in which the presence of carbon materials play an essential role. For these applications, surface chemistry plays a relevant role in the physical and chemical properties of carbon materials. Ionic liquids are intrinsic solvents and electrolytes. Because of the great interest in the potential of ionic liquids as alternative materials in diverse electrochemical applications, studies on the properties of molecular assemblies of ionic liquids have become important. Herein, we will report the surface modification of carbon materials by means of electrografting. Electrochemical processes based on oxidative or reductive grafting have been used for the attachment of organic molecules, such as redox active ionic liquids, onto various electrode surfaces providing new and special properties to the interfaces. The immobilization of redox active poly(ionic liquid) by surface-initiated atom transfer radical polymerization SI-ATRP process onto electrode surfaces has been investigated. The surface and electrochemical properties of these modified surfaces were investigated by combining different techniques (XPS, AFM, ellipsometry, and contact angle). We will show the use of redox active poly(ionic liquid) polymer brush as electrochemically reversible tunable surface wettability system and as electrochemical sensors for the detection of biomolecules.

Authors : Qin Cheng, Kangbing Wu*
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Resume : 3D hierarchical porous carbon was synthesized from a metal organic framework (MOF) formed by 1,4-benzenedicarboxylic acid and zinc nitrate hexahydrate using sugars as the carbon precursor. The morphology and pore characteristics were controlled by varying the carbon precursor, which is confirmed from SEM, TEM, Raman spectra, BET, TGA, and XRD. The electrochemical properties and analytical applications of the resulting 3D hierarchical porous carbon were systematically studied. It was found that the 3D hierarchical porous carbon exhibited greatly-increased electron transfer ability and accumulation efficiency as confirmed by electrochemical impedance spectroscopy and chronocoulometry. More importantly, the obtained porous carbon displayed strong surface enhancement effects, and greatly enhanced the oxidation signals of various analytes, such as dopamine, uric acid, catechol, hydroquinone, sunset yellow and amaranth. Thus the prepared porous carbon holds great promise in constructing a highly sensitive electrochemical sensing platform.

Authors : James Clark, Ying Chen, S. Ravi P. Silva
Affiliations : James Clark, S. Ravi P. Silva, Advanced Technology Institute, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom; Ying Chen, Department of Biochemistry and Physiology, University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom

Resume : In order to study electrical and chemical signals of individual cells in living organisms or tissues, we need to use electrodes with ≤20 µm diameter. However, electrodes of this size generally produce high impedance, even when the surface area is increased by using electroplated Pt or nanostructured TiN, both of which are commercially available. This relatively high impedance reduces the signal-to-noise ratio and hampers the recording of moderate electrical currents and chemicals released from individual cells. Therefore, this work aims to use as-grown carbon nanotubes (CNTs) as the electrode material to significantly improve on the impedance of commercially available electrodes. CNTs have high-aspect ratio, high conductance, relative chemical inertness and ability to be functionalised, therefore an ideal candidate for this application. Thus we created as-grown CNT electrode arrays (8 x 8) with each individual electrode of 20 µm diameter. The electrodes consisted predominantly of metallic single-walled CNTs, as demonstrated by Raman spectroscopy. Electrochemical impedance spectroscopy reported an impedance of 2.43 ±0.45 kΩ (N=8) at 1 kHz, which is a 10-fold improvement on commercially available electroplated Pt electrodes of the same size. These novel as-grown CNT electrodes will potentially allow increased sensitivity of bio-electrochemical detection.

Authors : Ju Fu, Xiaohong Tan, Zhen Shi, Xinjian Song, Shenghui Zhang
Affiliations : Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province, Hubei University for Nationalities, Enshi 445000, China; School of Chemical and Environmental Engineering, Hubei University for Nationalities, Enshi 445000, China

Resume : Pristine graphene was facilely prepared through one-step liquid-phase exfoliation of graphite powder in N,N-dimethylformamide with the assistance of sodium citrate. The resulting graphene dispersion was directly employed to modify the surface of glassy carbon electrode (GCE) via solvent evaporation. Subsequently, mercaptoacetic acid was electropolymerized onto the graphene sheets to easily construct an electrochemical sensor for sensitive and simultaneous detection of hydroquinone (HQ) and catechol (CC). By cyclic voltammetry (CV), the peak currents of HQ and CC increased obviously on the developed electrochemical sensor. Under optimal conditions, the oxidation peak currents of HQ and CC were linear over the range from 0.1 to 60 μM. The detection limits (S/N = 3) for HQ and CC were 80 and 85 nM, respectively. The fabricated sensor based on poly(mercaptoacetic acid)/exfoliated graphene composites showed satisfactory selectivity and stablility.

Authors : Luyun Jiang, John Foord
Affiliations : University of Oxford, Department of Chemistry

Resume : The effects of modifying a glassy carbon electrode with various forms of nanocarbon material for the electrochemical detection of phenolic compounds were studied. The nanocarbons considered included carbon black, graphene nanoplatelets and nanodiamond, for which the former two materials were found to show a large increase in the detection sensitivity. It was shown that the simultaneous detection of hydroquinone (HQ) and dihydroxybenzene (DHB) was possible using these electrodes, and in ‘real’ samples such as river water and green tea. Additional modification of the electrodes with tyrosine also permitted detection of phenol and p-cresol. The nanodiamond and carbon black modified electrodes were also employed for the electrochemical detection of Bisphenol A (BPA), which can be severely hampered by electropolymerisation of the oxidation products of BPA, producing rapid electrode fouling. It was also observed that for the carbon black modified electrode, a strong electrochemical response could be seen associated with the quinone forms produced by BPA oxidation. The associated electrochemical signal is also found to be relatively insensitive to electrode fouling, opening up an alternative strategy for the detection of BPA.

15:30 Coffee Break    
Carbon Interface : Hyacinthe Randriamahazaka
Authors : Yao Ma, Xiao Sun, Nianjun Yang,* Junhai Xia, Lei Zhang, Xin Jiang*
Affiliations : Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Carbon nanostructures are difficult to be synthesized with precisely controlled shapes. A facet-selective-catalytic process was thus proposed to prepare polymer-liked carbon nanostructures with different shapes, covering straight carbon nanofiber, carbon nano Y-junction, carbon nano-hexapus, and carbon nano-octopus. A thermal chemical vapour deposition process was applied to synthesize 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 via the selective growth of polymer-like sheets on certain indexed facets of Cu catalyst. The Vapor-Facet-Solid (VFS) mechanism, a new growth mode, has been proposed to interpret such a growth in the steps of formation, diffusion and coupling of carbon contained oligomers, as well as their final precipitation to form nanostructures on the selective Cu facets.

Authors : Xuerong Chen , Yikai Zhou*, Jiao Wang, Kangbing Wu*
Affiliations : School of Public Health, Tongji Medical College,Huazhong University of Science and Technology, Wuhan 430030, China; School of Chemistry and Chemical Engineering,Huazhong University of Science and Technology, Wuhan 430074, China

Resume : It is quite important to develop sensitive and simple analytical methods for heavy metal ions, such as Cd2+ and Pb2+. Herein, graphene nanosheets (GS) were easily prepared via one-step ultrasonic exfoliation of graphite powder in N-methyl-2-pyrrolidone (NMP). The obtained GS suspension underwent filtration and the resulting GS solid samples were redispersed into DMF. After that, the GS-DMF suspension was used to modify the surface of GCE by solvent evaporation. Compared with the bare GCE, the GS-modified GCE greatly increased the anodic stripping peak currents of Cd2+ and Pb2+, showing strong signal enhancement effects. Interestingly, the response signals of Cd2+ and Pb2+ on the GS film surface were further enhanced remarkably in the presence of Bi3+. Based on the synergistic enhancement effects of NMP-exfoliated GS and Bi film, a novel electrochemical sensor with high sensitivity was successfully developed for Cd2+ and Pb2+. The linear range for Cd2+ was from 0.6 to 20 µg L-1, and from 0.3 to 20 µg L-1 for Pb2+. Finally, this new sensing system was used in the analysis of different food samples such as porphyra and milk, and the results consisted with the values that obtained by ICP-MS.

Authors : Min Wang, Chao Ruan, Yongfu Lian
Affiliations : Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education,School of Chemistry and Materials, Heilongjiang University, Harbin 150080, China

Resume : Carbon nano-onions(CNOs) were fabricated by electric arc-discharge method with nickel powder as catalyst. The morphology and structure of the obtained samples were characterized by field-emission scanning electron microscope, transmission electron microscopy, Raman spectrum and X-ray diffraction. The results of cyclic voltammograms shows that the current peak value is related to the loading of CNOs on electrode surface. With the loading of CNOs the peak current value increases. Thus, it is estimated that the CNOs could provide accessible external surface area for ion adsorption.

Authors : Qing Guan, Wei Xiong, Lan Zhou, Shantang Liu, E-mail:
Affiliations : School of Chemistry and Environmental Engineering, Wuhan Institute of Technology, 693 Xiongchu Road, Wuhan 430073, P. R.China

Resume : A facile method was developed for the synthesis of nitrogen-doped porous carbon-gold (N-PCG) hybrid nanocomposite. For this method, the N-PCG was prepared by the polymerization of the oil-in-water emulsion (Span 80-Tween 80/1iquid paraffin/aqueous melamine-formaldehyde), then followed by carbonization. As-prepared samples were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller. The electrochemical properties of modified electrodes were conducted by cyclic voltammetry and electrochemical impedance spectroscopy. The N-PCG modified gold electrode has been prepared for the electrochemical determination of ultratrace mercury(II) in drinking water through square wave anodic stripping voltammetry (SWASV). The operational parameters which have influence on the deposition and stripping of metal ions, such as supporting electrolytes, pH value, deposition time and deposition potential were carefully studied. Under optimized conditions, the N-PCG modified electrode shows a sensitive detection to Hg ion present in concentrations of 0.001-1 μM, with a detection limit of 0.35 nM (S/N=3), which was much lower than the guideline values in drinking water given by the World Health Organization. The porous structure, fast electron transfer ability, and simple synthesis approach of N-PCG make it a promising electrode material for practical applications in heavy metal ion determination.

Poster Session : Quan Yuan, Dai-Wen Pang
Authors : Okoth Otieno Kevin, Kai Yan, Lan Liu, Jingdong Zhang
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Luoyu Road 1037, Wuhan 430074, P.R. China

Resume : A simple but sensitive electrochemical method was proposed for simultaneous determination of paracetamol (PCT) and diclofenac (DCF) based on poly(diallyldimethylammonium chloride) (PDDA) functionalized graphene (GR). Although electrochemical impedance analysis revealed that both GR and PDDA-GR modification could obviously facilitate the electron transfer on glassy carbon electrode (GCE), the electrochemical responses of PCT and DCF mixture on two modified electrodes were different. On GR modified electrode, the currents were enhanced while the oxidation peak difference between PCT and DCF was reduced, which led to a difficulty in the simultaneous determination of two drugs. By contrast, PDDA-GR greatly increased the electrochemical currents of both analytes while provided well-separated peak potentials. Thus, the simultaneous determination of PCT and DCF by differential pulse voltammetry was investigated on PDDA-GR. The applicability of the proposed method was verified when it was applied in determination of PCT and DCF in pharmaceuticals and lake water. Good reproducibility and high stability were also achieved.

Authors : Yi Liu†, Zhaohao Wang†, Qijin Wan†,*, Nianjun Yang†,‡*
Affiliations : †School of Chemistry and Chemical Engineering, Wuhan Institute of Technology, Wuhan 430073, China ‡ Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Graphene nano platelets (GNPs) or nano graphene platelets (NGPs) are stacks of graphene sheets with an overall thickness ranging from an average of about 5 to about 25 nm. Most of them have "platelet" morphology with a diameter of 0.5 to 25 μm. Their aspect ratios are high and can be range into the thousands. They show similar thermal and mechanical properties to CNTs but their surface areas or aspect ratios are higher. They have therefore different properstes from single or few (up to 5) layered grapheme. They have been more widely applied for various applications, such as electrochemical detections and biochemical sensing. However the properties are expected to be different from. In this presentation, we will show electrochemical deposition of gold-palladium nanoparticles (AuPd NPs) on graphene-nano-platelets (GNPs) and their application for electrocatalytic oxidation of hydrazine. The deposition was conducted using a potentiostatic mode in a mixture of HAuCl4 and H2PdCl4. This composite was characterized using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), and electrochemical impedance spectroscopy (EIS). AuPd NPs are well-dispersed on the GNP surface with particle diameter of about 30-60 nm. Moreover, they are alloyed and have porous structures. Their application was focused on the voltammetric detection of hydrazine. The chronoamperometric (CA) and cyclic voltammetric (CV) curves proved the catalytic ability of AuPd NPs towards the electrochemical oxidation of hydrazine. Under the optimized conditions, the oxidation current is linear with the concentration of hydrazine in the range of 0.02 - 166.6 μM with a sensitivity of 62.2 μA mM-1 and a detection limit of 5 nM. These results will be compared and discussed as well with those published in literature.

Authors : Yanying Wang, Miao Han, Kangbing Wu, Chunya Li
Affiliations : a.South–Central University for Nationalities; b. Huazhong University of Science and Technology

Resume : A novel ionic liquid, 3-{3-[(2-Aminoethyl)amino]propyl}-1-vinylimidazole bromide, was synthesized and used as a functional monomer for the fabrication of a molecularly imprinted sensing interface for myoglobin. Using the as-prepared ionic liquid as functional monomer, myoglobin from skeletal muscle as template, N,N’-Methylenebisacrylamide as crossing linker, and a redox system containing ammonium persulfate and N,N,N’,N’-Tetramethylethylenediamine as initiator, a myoglobin imprinted film was in-suit fabricated on a multiwall carbon nanotubes modified glassy carbon electrode surface at room temperature. Based on the electroactive probes, K3[Fe(CN)6]/K4[Fe(CN)6], the electrochemical sensing performances of the molecularly imprinted film electrode were investigated. The results demonstrated that the molecularly imprinted film possesses good selectivity and high sensitivity. The peak current variation is linearly related to the myoglobin concentration in the range from 6.0 10-8 to 6.0 10-6 mol L-1. The detection limit was calculated to be 9.68 10-9 mol L-1(S/N=3). Acknowledgments The authors gratefully acknowledge the financial supports from National Natural Science Foundation of China (No.21275166), China Scholarship Council (No. 201307780006), and the Natural Science Foundation of Hubei Province (No. 2015CFA092).

Authors : Yuanyuan Zhang, Xin Liu*, Qin Cheng, Piaopiao Wei, Kangbing Wu*
Affiliations : College of Life Science and Technology , Huazhong University of Science and Technology, Wuhan 430074, China; School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Resume : Porous carbon was prepared using CaCO3 nanoparticles as the hard template and starch as the carbon precursor, and then used to modify the surface of glassy carbon electrode (GCE). The morphology and porous structure were confirmed using SEM and TEM. Electrochemical responses of K3[Fe(CN)6] revealed that porous carbon was capable of facilitating electron transfer and increasing surface area. Electrochemical behaviors of Salvianolic acid B were studied, and a sensitive oxidation peak was observed in pH 7.0 phosphate buffer. Compared with the bare GCE, the porous carbon-modified GCE greatly increased the oxidation peak current of Salvianolic acid B, showing remarkable signal enhancement effect. The influences of pH value, amount of porous carbon, accumulation potential and time on the oxidation peak currents of Salvianolic acid B were studied. As a result, a novel electrochemical method was developed for the determination of Salvianolic acid B. The linear range was from 5 to 1000 μg L-1, and the detection limit was 0.27 μg L-1. Finally, this new sensing system was used in traditional Chinese medicines, and the results consisted with the values that obtained by high-performance liquid chromatography.

Authors : Tian Gan ,Zhaoxia Shi
Affiliations : Collegeof Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China

Resume : As we know, maltol has been widely found in foods and beverages and used as a flavor enhancer to improve the taste. But an overdose of maltol exhibits a certain toxicity that may cause adverse reactions such as headache, nausea or vomiting. In addition, maltol can bind aluminum to form a stable and neutral complex, which significantly increases the absorption of aluminum by about 20 times higher than usual. A variety of techniques have been developed to detect maltol now, such as spectrophotometry, two–dimensional (2D) liquid chromatography, gas chromatography–mass spectrometry, high–performance liquid chromatography, chemiluminescence, and electrochemistry. Among them, electrochemical techniques are preferred because of their rapid response, convenient use, high sensitivity, good selectivity, time saving and low cost. Graphene oxide (GO) has attracted tremendous interests since being discovered due to its outstanding properties, such as thermal and chemical stability, excellent electronic conductivity, large specific surface area, enhanced electrocatalytic activity and water solubility. Therefore, GO was used in electrode surface modification as an extraordinary choice for target molecule detection. Here, We reported a rapid–response and high–sensitivity electrochemical sensor with specificity toward maltol, based on GO–wrapped amino–functionalized carbon sphere (ACS) hybrid as the conductive channel. The GO–ACS hybrids were characterized using Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy. The results indicated that a well–organized structure was successfully prepared, based on specific electrostatic attractions between the ACS and the GO nanosheets. Next, a sensitive and selective electrochemical sensor was successfully constructed for the direct detection of maltol by casting a GO–ACS film onto the surface of a glassy carbon electrode. The oxidative peak current increased linearly with the concentration of maltol in the range of 0.1 M~0.8 mM using differential pulse voltammetry, and the detection limit was 24 nM with S/N = 3. Furthermore, the sensor was applied to determine the maltol content in wines. The recoveries of the sensors varied from 93.1 to 104, indicating that the prepared sensor might be promising for the determination of maltol in food–safety monitoring.

Authors : Tian Gan, Zhen Lv
Affiliations : College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China

Resume : Manganese compounds have been often used as efficient catalysts toward oxidation reaction, and as we all know, they are widely abundant in nature. Among the large variety of morphologies, manganese−based hollow structures stand out as a class of interesting materials, since they may exhibit improved catalytic properties owing to significant increase in their surface area to volume ratio. p−Aminophenol and o−aminophenol are recognized as serious environmental pollutant and may cause general itching, skin sensitization, dermatitis, and allergic reactions. A critical survey of the literature reveals that few methods are developed for the simultaneous determination of p−aminophenol and o−aminophenol. Amino phenols are amphoteric, which involve aromatic amino group, phenolic hydroxyl moiety as well as substitution on the benzene ring, which provide theoretical support for making use of electrochemical sensors to detect p−aminophenol and o−aminophenol based on redox properties of amino phenols. Here, we developed a new electrochemical sensor for simultaneous determination of p−aminophenol and o−aminophenol based on hollow manganese silicate compounds with the morphology of nanobubbles within a microbubble, as confirmed by field emission scanning electron microscopy and transmission electron microscopy images. The preparation procedures for hollow manganese silicate compounds and the performance of the sensor were studied in detail. Under the optimized conditions, the linear range for p−aminophenol detection was 0.555 μM in the presence of 10.0 μΜ o−aminophenol, and the linear range of o−aminophenol was 0.5070 μM in the presence of 5.0 μΜ p−aminophenol. In particular, the detection limits (S/N = 3) for p−aminophenol and o−aminophenol were as low as 4.19 and 23.3 nM, respectively. Finally, the sensor was used in several water samples to evaluate its practical application, and the results showed recoveries between 91.80% and 105.43%, suggesting that this sensor is effective and reliable.

Authors : Guosong Lai, Hui Cheng, Cuiying Yin, Haili Zhang, Aimin Yu
Affiliations : Hubei Normal University

Resume : Recently, the development of nanoprobe signal amplification based ultrasensitive electrochemical immunoassay methods has shown a promising perspective in the clinical diagnosis field. Compared with the conventionally used enzymatic signal tags, gold nanoparticle (Au NP) has gained more and more attentions as a ideal nonenzymatic tags due to unique properties. In this work, we sucessfully designed a novel Au NP-functionalized graphene nanoprobe for the signal tracing of immunoassay and thus developing a new ultrasensitive electrochemcial immunoassay method. The nanoprobe was prepared through the in situ deposition of Au NPs on the surface of graphene oxide (GO) which was followed by the hydrothermal reduction to form a reduced graphene oxide (rGO)-Au NPs nanocomposite. After the antibody functionalization, the obtained rGO-Au NPs based nanoprobe was used for the signal tracing for the sandiwich immunoassay at a carbon nanotubes-modified electrode based immunosensor. The high-content Au NP tags on the quantitatively captured rGO-Au NPs nanoprobes via immunoreaction could be coveniently measurment through electrochemical stripping analysis to produce sensitive electrochemcial signal for quantitativel immunoassay. Due to the signal amplificaiton of the nanoprobe and the electron transfer acceleration of the carbon nanotubes modified on the electrode surface, ultrahigh sensitivity for the protein analyte measurement was achieved. As this gold nanoprobe is simple and cheap for preparation, and the Au NPs stripping analysis is convenient for manipulation, this nanoprobe and the developed immunoassay method provide great potentials for practical applications.

Authors : Wanyun Gong, Jing Zou, * Sheng Zhang, Xin Zhou, Jizhou Jiang
Affiliations : School of Chemistry and Environmental Engineering, Wuhan Institute of Technology

Resume : The nickle oxide and nickle co-doped graphitic carbon nitride (NiO-Ni-GCN) nanocomposites were successfully prepared by thermal treatment of melamine and nicklechloride hexahydrate. The NiO-Ni-GCN nanocomposites showed superior the electrochemical catalytic activity for the oxidation of octylphenol to pure GCN. A detection method of octylphenol in environmental water samples was developed based at the NiO-Ni-GCN nanocomposites modified electrode . Differential pulse voltammetry was used as the analytic technique of octylphenol, exhibiting stable and specific concentration-dependent oxidation signal in the presence of octylphenol in the range of 10 nM to 50 μM, with a detection limit of 3.3 nM (3S/N). The fabricated electrochemical sensor was successfully employed to the detection of octylphenol in lake water samples.

Authors : Weihua Wang,ZHaojun Wu, Yanfang Gao*, Lijun Li*, Jinrong Liu
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology

Resume : A designed rod-shaped CeO2 (NRCeO2) was successfully synthesized by in situ growth method on the graphene sheets (GNs), which act as a spacer to prevent graphene stack. When graphene sheets which has grown rod-shaped CeO2 and also embellished with Pt nanoparticles are continuously stacked on each other, a three-dimensional (3D) layer-by-layer Pt-NRCeO2/GNs composite structure is created. For TEM and SEM characterization, the 3D structure has been confirmed. In the electrochemical tests, the as-designed 3D Pt-NRCeO2/GNs catalyst shows the highest ESA value (72.6 m2 g-1) and the largest catalytic current density (498 mA mg-1) for methanol oxidation compared with other catalysts. Due to the effect of rod-shaped CeO2 which act as a spacer to prevent graphene stack, a large amount of Pt particles are exposed to the electrolyte solution. It shows that a designed 3D Pt-NRCeO2/GNs composite structure is an efficient way to improve the electrocatalytic performance.

Authors : Yuanbin Tan, Yaohua Li, Zhen Shi, Jinshou Wang, Shenghui Zhang, Changzhu Yang, Jingdong Zhang
Affiliations : Huazhong University of Science and Technolgoy, School of Chemical and Environmental Engineering, Hubei University for Nationalities

Resume : The aim of this work was to construct an electrochemical sensor for the detection of bisphenol A (BPA) by using molecularly imprinted technique. In order to enhance the sensitivity of the sensor, acetylene black was introduced during the preparation of imprinted sensor owing to its unique properties involving huge surface area, strong adsorptive ability, subtle electronic properties and catalytic ability. A electrochemical sensor for the determination of BPA has been developed via drop-coating method to form a thin molecularly imprinted chitosan film doping with acetylene black on the surface of a glassy carbon electrode (GCE). Several important parameters controlling the performance of the sensor were investigated and optimised. The sensor responds linearly to BPA in the 70nM to 20 μM concentration range, and the detection limit is 50 nM (S/N=3). This sensor shows a high degree of sensitivity, and broad linear measuring range. In addition, it showed good selectivity, repeatability and stability. The sensor was employed to detect BPA in real plastic samples successfully.The construction of this sensor is relatively simple and it provides a rapid and economical electrochemical method for the determination of BPA. The study provided a practical method in BPA analysis and a promising approach in sensor preparation.

Authors : Zhijie Wang, BeibeiLi, QijinWan,
Affiliations : School of Chemistry and Environment Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Wuhan Institute of Technology, Wuhan 430073, China

Resume : A graphene/ferrocene/sol–gel silica nano-interface has been constructed to develop glucose biosensor. An electro-assisted co-deposition process was applied. Using such a single electrochemical step in which the ferrocene mediator, graphene and glucose oxidase were immobilized simultaneously in the sol-gel film. This film was characterized using scanning electron microscope and electrochemical techniques. Well-defined ferrocene response and better glucose sensing are found on this film. Using amperometry, the analytical performances of this glucose biosensor was studied. The glucose biosensor shows a linear response to glucose concentration in the range from 5×10-6 to 1.5×10-2 M with a correlation coefficient of 0.996.The detection limit is calculated to be 1.6 µ M (S/N=3). The sensitivity is about 16 A mM-1 cm-2

Authors : Jiaqi Fan, Guohua Zhao
Affiliations : Department of Chemistry, Tongji University, Shanghai 200092, China

Resume : A novel three-dimension macroporous-mesoporous (3DOM-m) TiO2 / 3DOM-m Sb-doped SnO2 electrode with excellent photoelectrocatalytic oxidation performance is fabricated on the boron-doped diamond (BDD) substrate through the polystyrene sphere (PS) vertical deposition method, which used for photoelectrochemical organic contaminant degradation. SEM, and XRD revealed that 3DOM-m electrode possessed three dimensional macroporous layered structure, high effective surface area and nanosized particles. Through in-depth investigation of electrochemical and photocatalytic properties by EIS, LSV and CV tests, the electrode exhibits outstanding electrochemical activity and photo-to-current conversion efficiency. The 3DOM-m electrode is further served in bisphenol A (BPA) removal. Compared with other electrodes, BPA is completely decompose on the 3DOM-m electrode with large corresponding kinetic constant. Collectively, the as-prepared three-dimensional structured electrode which is an efficient photoelectrochemical electrode can potentially be applied for industrial wastewater electrolysis.

Authors : Tiantian Xia, Gang Chang, Jie Su, Hongmei Jia, Yingying Zhou, Yunbin He
Affiliations : Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, Faculty of Materials Science and Engineering, Hubei University, No.368 Youyi Avenue, Wuchang, Wuhan 430062, China

Resume : Recently, enormous attention focuses on direct methanol fuel cells (DMFCs) due to its high energy density, portability and environmental sustainability. Especially, carbon-supported noble metal nanoparticles of anode catalysts become an advanced research topic. Graphite nanoplates can be acted as an attractive supporting material for coupling with noble metals because of its extraordinary conductivity and high specific surface area. Although many methods have been developed to generate graphene, exploiting a simpler and effective way is still a huge challenge. Herein, we use a simple and rapid method to exfoliated graphite. Uniform and ultra-fine Pd nanoparticles supported on graphite nanoplates (Pd/GN) have been successfully synthesized by the reduction of sodium borohydride. In this process, graphite was firstly pre-oxidized by concentrated sulfuric acid, potassium persulfate and phosphorus pentoxide, and then ultrasonically exfoliated by N-methyl-2-pyrrolidone. Small size of Pd nanoparticles supported on graphite nanoplates were successfully prepared by a simple one-step method with no organic solvents or surfactant agents. The as-prepared nanocomposite has been characterized by transmission electron microscopy and electrochemical measurements for methanol oxidation. Compared to the commercial Vulcan XC-72 and reduction graphene oxide supported nanoparticles, Pd/GN shows superior electrocatalytic activity for methanol oxidation, which makes them promising for DMFCs.

Authors : Su Li a, Ying Xiong b, Bing Wang b,*, Changgen Feng a,*
Affiliations : a State Key Laboratory of Explosion Science and Technology, School of Mechatronical Engineering, Beijing Institute of Technology, Beijing 100081, P. R. China b State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010, P. R. China

Resume : Adsorptive stripping voltammetry (ASV), in the presence of suitable complex agents, is an effective approach in determining uranyl ions in the environment. Normally, poisonous mercury electrode is employed during the detection process. In this contribution, boron-doped diamond (BDD) is used as an environmental friendly alternative electrode to ASV analysis of uranyl ions. Under optimal conditions, a wide linear relationship over the concentration range from 1 ppb to 10 ppm can be obtained and a very low detection limit of about 0.012 ppb has been calculated by the standard 3 method. The low relative standard deviation for 0.5 (0.30%), 2.5 (0.98%) and 10 (0.68%) ppm uranyl ions suggests BDD electrode has good reproducibility and sensitivity. In addition, the potential interferences of several metal ions in solution are also investigated and the results confirm the possibility of uranyl ion determination in water samples containing high concentrations of metal ions.

Authors : Xiaofeng Yang, Jianghua Long, Dong Sun*
Affiliations : Xiaofeng Yang, Jianghua Long, Dong Sun* School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou 325035, China

Resume : Graphene nanosheets (GS) were easily prepared by ultrasonic exfoliation of graphite powder in N-methyl-2-pyrrolidone (NMP), which was characterized using TEM. The resulting GS was used to modify the surface of glassy carbon electrode (GCE) via solvent evaporation. The measurements of SEM and AFM indicated that the modification of GS enahances the surface roughness, and consequently increases the response area and electrochemical reactivity. The electrochemical behaviors of rutin were studied, and a sensitive oxidation peak was observed on the GS-modified GCE (GS/GCE). Compared with the unmodified GCE, the GS/GCE greatly enhanced the oxidation signals of rutin, showing remarkable signal enhancement effects. The influences of pH values, amount of GS, accumulation potential and time were examined, and a highly-sensitive electrochemical sensor was developed for rutin. The linear range was over the range from 10 nM to 1.5 M, the limit of detection is 5 nM. The proposed method was used in the sample analysis of traditional Chinese medicines, and the detected results consisted with the values of that obtained by high performance liquid chromatography.

Authors : Yongkang Ye1,2, Houchuan Xu1, Xuan Sun1, Xiaodong Cao1,2,*, Guoqing Liu1,2, Xiaoguang Ge3,*
Affiliations : 1. School of Biotechnology & Food Engineering, Hefei University of Technology, Hefei 230009, China 2. Wanjiang Institute of Poultry Technology, Hefei University of Technology, Xuancheng Campus, Xuancheng 242000, China 3. School of Resource & Environmental Engineering, Hefei University of Technology, Hefei 230009, China

Resume : Hydrogen sulfide (H2S), a kind of poisonous gas which can be found in forms of dissolved H2S, HS- and S2- in aqueous medium, is demonstrated to be a potential food preservation gas for prolonging postharvest shelf life of fruits [1] and vegetables [2]. It is necessary to develop fast and effective detection of these forms of H2S (classified as sulfides) that possibly remained in food in case of harm. In this work, we presented a new approach for rapid detection of sulfide using a glassy carbon electrode (GCE) modified with alizarin (Az) and reduced graphene oxide (rGO) nanosheets. The fabricate Az-rGO/GCE sensor exhibited a notable electrocatalytic activity to sulfide oxidation. Amperometric studies showed that the steady currents were related linearly to the concentrations of sulfide in the range of 0.05 to 2.25 mM. The proposed method was successfully applied in sulfide determination of hydrogen sulfide pretreated fruits, and the method was verified with recovery studies with recovery values of 91%-121%. Fig. 1. Amperometric responds to the different concentrations of sulfide on Az-rGO/GCE at applied potential of +0.225 V (vs. Ag/AgCl). Inset: TEM image of reduced graphene oxide. Reference [1] L.Y. Hu, S.L. Hu, J. Wu, Y.H. Li, et al. J. Agric. Food Chem. 2012, 60, 8684−8693 [2] S.P. Li, K.D. Hu, L.Y. Hu, et al. J. Agric. Food Chem. 2014, 62, 1119−1129

Authors : Yanbin Wang, Guohua Zhao*
Affiliations : Department of Chemistry, Tongji University, Shanghai 200092, China

Resume : Fe3O4-containing ordered mesoporous carbon (Fe3O4@OMC) was successfully prepared using iron(III) acetylacetonate as iron source and grafted onto carbon aerogel to form composites electrode (Fe3O4@OMC/CA). High-resolution transmission electron microscopy (HRTEM) showed Fe3O4 nanoparticles highly dispersed into the matrix of ordered mesoporous carbon. The Fe3O4@OMC/CA and boron-doped diamond (BDD) were used as cathode and anode for the electro-Fenton degradation of dimethyl phthalate (DMP). The Fe3O4@OMC/CA showed excellent electrocatalytic activity for DMP treatment and 82% mineralization of DMP was achieved in 120 min. The main oxidants are hydroxyl radicals (•OH) formed from water oxidation at the BDD anode and Fenton-like reaction between Fe3O4 and H2O2 generated at the surface of OMC/CA. In addition, the degradation mechanism of DMP was also proposed. The composites electrode remained good electrocatalytic activity even after five consecutive runs and could be a promising candidate as heterogeneous electro-Fenton materials for organic contaminants removal.

Authors : Siyu Yu, Yao Ma, Nianjun Yang*, Hao Zhuang, Xin Jiang*
Affiliations : Institute of Materials Engineering, University of Siegen, Paul-Bonatz-str.9-11, 57076 Siegen, Germany

Resume : Boron-doped diamond is a promising electrode and electrode support for electrochemical capacitor applications. In this presentation we will show the applications of diamond for electrical double layer capacitor and pseudosupercapacitors. The capacitance of diamond based electrical double layer capacitor only reduced 5% even after 1 000 charge-discharge cycles in 1.0 M sodium sulphate solution at a scan rate of 100 mV/s. To improve the performance of diamond based capacitors, large surface areas of diamond electrodes (for electric double layer capacitors) or diamond based composite films (for pseudosupercapacitor) are required. Carbon nanofibers on diamond electrode surface will be shown for electric double layer capacitor application as well as manganese dioxide coated diamond electrode for pseudosupercapacitor application. Carbon nanofibers were grown using thermal chemical vapour deposition method with aid of copper nanoparticles as the catalysts. Manganese dioxide was electrochemically deposited on diamond electrode at a constant potential. The charge consumed during the deposition was applied to control the amount and the thickness of manganese dioxide on the diamond electrode. The performance of two capacitors will be shown in details. The comparison of carbon nanofibers based double layer capacitor with manganese dioxide based pseudosupercapacitor as well as with those related capacitors shown in literature will be conducted. More regarding the life-time of these capacitors, power and energy densities, etc. will be discussed as well.

Authors : Yi Liu, Zhaohao Wang, Qijin Wan*
Affiliations : 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

Resume : Gold-palladium nanoparticles (AuPd NPs) were prepared on a layer of graphene film by potentiostatic electrodeposition from a mixture electrolyte of HAuCl4 and H2PdCl4 to fabricate the AuPd NPs/graphene/glass carbon electrode (AuPd/GR/GCE). The synthesized composite has been characterized using scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX). The results showed that metal nanoparticles were alloy nanoparticles and well-dispersed on the surface of graphene, with particle diameter of about 30-60nm. Electrocatalytic oxidation of hydrazine on the surface of modified electrode was investigated with cyclic voltammetry and chronoamperometry methods, the results showed that the AuPd NPs’ high catalysis for the electrochemical oxidation of hydrazine and the excellent conductivity of graphene. Electrocatalytic activity of the modified electrode was investigated for the oxidation of hydrazine in 0.1 M phosphate buffer solutions (pH=6.0). Under the optimized conditions, the oxidation current of hydrazine was linear to its concentration in the range of 0.02–166.6 μM with a sensitivity of 62.2 μA mM-1, and the estimated detection limit was 5 nM (S/N =3).

Authors : Yanying Wang; Rui Li;Chunya Li*
Affiliations : College of Chemistry and Materials Science, South–Central University for Nationalities

Resume : 1,3-di(4-amino-1-pyridinium) propane tetrafluoroborate ionic liquid (DAPPT) was successfully synthesized and characterized by NMR, HPLC-MS. DAPPT was used as a modifier to functionalize reduced graphene oxide (rGO) nanosheets. DAPPT-rGO nanosheets and tyrosinase (Tyr) were thoroughly mixed, and coated to glassy carbon electrode to fabricate a Tyr-DAPPT-rGO/GCE modified electrode, which would be a promising biosensor for phenolic compounds. The as-prepared modified electrodes were characterized with scanning electronic microscopy and electrochemical impedance spectroscopy. Using bisphenol A (BPA) as a target molecule, a number of key factors including the volume of Tyr-DAPPT-rGO solution, the applied potential, pH values and temperature that influence the analytical performance of the biosensor were investigated. The biosensor gave a linear response on the BPA concentration in the range of 1.0 × 10-9 ~ 3.8 × 10-5 molL-1. The detection limits were estimated to be 3.5 × 10-10 molL-1 (S/N=3). Practical application of the biosensor was demonstrated by the determination of BPA leaching from commercial plastic drinking bottles. Results indicated that Gr-DAPPT based interface would be a promising platform for biosensor preparation.

Authors : S. Revo (a), V. Chornii (a), M. Nedielko (b), Yu. Sementsov (c)
Affiliations : (a) Taras Shevchenko National University of Kyiv, Volodymyrska Street 64/13, 01601, Kyiv, Ukraine; (b) E.O. Paton Electric Welding Institute of NASU, Kyiv, Ukraine; (c) Chuiko Institute of Surface Chemistry, NASU, Kyiv, Ukraine

Resume : Various types of graphene preparation are well known up to now. The mechanical exfoliation of HOPG graphite; nano-diamond – and SiC- based precursor methods, CVD growth using metal catalysts, such as Ni, Cu, etc. In spite that, development of new methods for fabrication of graphene – like structured materials is still under investigation, as a graphene families of materials prepared with different methods reveal somewhat different properties. We used modified electro-chemical dispersion, called by us as electro-chemical exfoliation method, to prepare graphene containing material in the shape of colloid system. Raman spectroscopy, optical, AFM, STM, and SEM microscopy were applied for characterization of both freely suspended and extracted carbon particles sitting on various substrates (like glass, Si, quartz) as well. Luminescence studies were also performed for suspended particles and for flakes on glass or quartz substrates and for aggregated flakes too. The conclusion was made that ensemble of particle consists of large particle those posses graphite structure and some quantity of graphene – type flaks. Dependences of the characteristics on the concentration, chemical treatment, size, and thickness of carbon micro- and nanoparticle stacking were obtained and analyzed.

Authors : Lijun Li, Xiaoyan Wang, Shujuan Wang, Yanfang Gao*, Jinrong Liu
Affiliations : College of Chemical Engineering, Inner Mongolia University of Technology

Resume : Active carbon derived from lignite was activated by ZnCl2, which showed high double capacity performance in a three electrode system. The result of SEM and BET refered that the material activated with ZnCl2 has more meso-pore than that activated with NaOH. Electrochemical investigations indicate that the activated carbon shows the maximum specific capacitance of 207.5Fg−1 in 6M KOH electrolytes at 0.5A g−1, respectively. The capacitor use activated carbon as electrode presents good cycle stability during 3,000 cycles at a fair current density of 5 A g−1 and capacity rate can reach 91%, because of its specific surface area of 1024 m2 / g.

Authors : Xili Tong, Xiaoning Guo, Xiangyun Guo*
Affiliations : State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, PR China.

Resume : Vertically oriented TiO2 nanotube arrays (TNTAs) were conformally coatedwith an ultrathin nitrogen-doped (N-doped) carbon filmvia the carbonization of a polyimide filmdeposited bymolecular layer deposition and simultaneously hydrogenated, thereby creating a core/shell nanostructure with a precisely controllable shell thickness. The core/shell nanostructure provides a larger heterojunction interface to substantially reduce the recombination of photogenerated electron–hole pairs, and hydrogenation enhances solar absorption of TNTAs. In addition, the N-doped carbon film coating acts as a high catalytic active surface for oxygen evolution reaction, as well as a protective film to prevent hydrogen-treated TiO2 nanotube oxidation by electrolyte or air. As a result, the N-doped carbon film coated TNTAs displayed remarkably improved photocurrent and photostability. The TNTAs with a N-doped carbon film of 1 nm produces a current density of 3.6 mA cm2 at 0 V vs. Ag/AgCl under the illumination of AM 1.5G (100 mW cm2 ), which represents one of the highest values achieved with modified TNTAs. Therefore, we propose that ultrathin N-doped carbon film coating on materials is a viable approach to enhance their PEC water splitting performance.

Authors : Ana Sánchez Grande, Daniel Arenas-Esteban, David Ávila-Brande, Esteban Urones-Garrote, Javier Carretero-González,L. Carlos Otero-Díaz
Affiliations : Department of Inorganic Chemistry, Faculty of Chemistry, Universidad Complutense de Madrid, E–28040, Madrid, Spain. ICTS Centro Nacional de Microscopía, Universidad Complutense de Madrid, E–28040, Madrid, Spain. Polymer Ionics Research Group, Warsaw University of Technology, Warsaw, Poland

Resume : One of the ways to enhance the capacitive properties of the carbon-based materials consists on the introduction of heteroatoms into the porous structure of high surface area carbon materials. Among them, heteroatoms such as Nitrogen will chemically bond to other carbon atoms in the aromatic structure of graphene modifying the electrochemical properties of the porous carbons. The presence of Nitrogen creates innovative carbon materials exhibiting double-layer capacitance due to its high surface area and fast reversible charge transfer reactions (pseudocapacitive) resulting from the nitrogen-redox pairs in the carbon.. Here, for the first time, the chlorination reaction, which is widely used to prepare carbon materials from metal carbides and organometallic precursors, allow us to prepare nitrogen-containing, up to 8% of N, porous carbon materials by using Cu, Fe and Ni pthalocianines as precursors. Their structural features as function of the chlorination temperature as well as the electrochemical performance in protic electrolytes of the Phtalacianine-derived nanoporous carbons have been investigated.

Start atSubject View AllNum.
Carbon for photoelectrochemistry : Paul May
Authors : Yong Liu, Yuhan Zhu, Kai Yan, Okoth Otieno Kevin, Jingdong Zhang *
Affiliations : School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, P. R. China

Resume : As a newly emerged but promising analytical technique, photoelectrochemical (PEC) detection based on photon-to-electricity conversion has attracted considerable interest due to its high sensitivity as well as simple and cheap instrumentation. To fabricate PEC sensors, various photoactive materials have been explored as transducer species which can convert photoirradiation to electronic response. Among various photoactive materials, graphite-like carbon nitride (g-C3N4) and graphene quantum dots (GQDs) can represent the new carbon nanomaterials-based photocatalysts that possess high photon-to-electricity conversion efficiency under visible light irradiation. We employed g-C3N4 and GQDs to construct two aptamer sensors, respectively, for PEC determination of kanamycin and chloramphenicol. On the other hand, graphene (GR) possesses high electrical conductivity. When GR was doped into CdS QDs, the PEC performance was obviously promoted. Based on the hybrid film of GR-CdS QDs, PEC sensors for 4-aminophenol, catechol and p-phenylenediamine were successfully developed.

Authors : Meichuan Liu, Jing Yu, Xue Ding, Guoqiang Wang, Guohua Zhao
Affiliations : Department of Chemistry, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, China

Resume : Graphene is a monolayer of tightly packed carbon atoms that possesses many interesting physical, chemical, electric and optical properties and has many exciting applications. Microcystin-LR (MC-LR), as inert electrochemical species released by cyanbacteria during eutrophication, is hard to be detected by a simple and direct electrochemical method. In our recent studies, an electrochemical aptasensing strategy based on enzyme assisted graphene assembly signal cycling amplification towards MC-LR has been proposed. Graphene is used in the system with bi-functions. It is first used to adsorb MC-LR binding aptamer to form aptamer-graphene (Apt-G) composites due to the strong - interaction. Once there’s target MC-LR in the system, the aptamer will be grasped by MC-LR and desorpt from graphene surface, leaving “naked” graphene in the solution, which can assemble onto MCH/Au because of the hydrophobic interaction and  conjunction, and can turn on the electron transfer route, resulting in signal generation and electrochemical quantification of MC-LR. Also, another photoelectrochemical aptasensor for MC-LR have been designed and constructed on graphene functionalized TiO2 nanotubes. Graphene is successfully grown onto highly ordered TiO2 nanotubes by a Clicked Chemistry way. MC-LR binding aptamers are further assembled via - interaction resulted from graphene. A promising photoelectrochemical aptasensing platform towards MC-LR under visible-light illumination has thus been provided on the graphene functionalized TiO2 NTs. (Acknowledgements: National Natural Science Foundations of China (NSFC) (No. 21377092)

Authors : Mailis M. Lounasvuori, Martin Rosillo-Lopez, Christoph G. Salzmann, Daren J. Caruana and Katherine B. Holt
Affiliations : Department of Chemistry, University College London, 20 Gordon St, London WC1H 0AJ, United Kingdom

Resume : Graphene nanoflakes (GNF) with lateral dimensions of ca. 30 nm and edge-terminated with carboxylic acid (COOH) or amide functionalities have been characterised electrochemically after drop-coating onto a boron-doped diamond (BDD) electrode. In the presence of the outer-sphere redox probe ferrocene methanol there is no discernible difference in electrochemical response between the clean and GNF-modified BDD. When hydroquinone or ferricyanide are used as redox probes there is a marked difference in response at the COOH-terminated GNF electrode compared to the unmodified BDD and BDD modified with amide-terminated GNF. The response of the COOH-terminated GNF electrode is highly pH dependent, with significant differences in response noted at pH < 8, where partial protonation of the acid groups is observed. The protonation state of the GNF influences the oxidation mechanism of hydroquinone and in particular the number of solution protons involved in the redox reaction. The voltammetric response of ferricyanide is inhibited at COOH-terminated GNF electrode at pH < 8, especially in low ionic strength solution. The redox reaction is much less influenced by the presence of GNF in D2O, highlighting the role played by readily available protons in destabilising the ferri/ferrocyanide couple. In the presence of GNF in solution, an additional, very intense cyanide stretch IR band is observed and attributed to the formation of a new, non-soluble species.

Authors : Xili Tong, Xiaoning Guo, Xiangyun Guo
Affiliations : Institute of Coal Chemistry, Chinese Academy of Sciences

Resume : Efficient electrocatalysts of copper nanoparticles with 5−15 nm mean size range on graphene support are successfully developed for controllably catalyzing CO2 electroreduction reactions, and their catalytic activity and selectivity during CO2 electroreduction were analyzed and compared to a bulk Cu electrode. An obvious increase in the catalytic activity was observed with decreasing Cu particle size. This is likely due to an increase in the fraction of under-coordinated sites, such as corners, edges, and defects, as the nanoparticles become smaller.

10:15 Coffee Break    
Diamond : Marcin Opllo
Authors : Xin Jiang, Hao Zhuang
Affiliations : Shenyang National Laboratory for Materials Science, Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS), No.72 Wenhua Road, Shenyang 110016 China

Resume : Diamond is known for its outstanding physical and chemical properties, making it promising for a wide range of applications. Recently, a strong demand in the fabrication of porous structures from diamond arises, because of its potential applications in the energy and environment related areas. However, the high chemical and physical stabilities of diamond as well as its extreme fabrication conditions make this task difficult. In the present contribution, we demonstrate the successful fabrication of porous diamond films with 3 dimensional interconnected pores via a template-free composite approach. It combines the deposition of diamond/β-SiC nanocomposite film with a wet-chemical selective etching of the β-SiC phase. Both undoped and boron doped porous diamond films are obtained. SEM, TEM and Raman analysis are carried out to monitor the whole etching process. Wide range tunability in the porosity, ranging from 15 to 68%, is achieved by controlling the diamond/β-SiC ratios in the composite films, which results in a significant enhancement in the surface area of diamond. For a porous diamond with 64% porosity, a surface area enhancement of 163 per micrometer thickness is obtained, as estimated by electrochemical method. Noticeably, the basic physical and chemical properties of diamond are not influenced by the introduction of pores, because of the high stability of diamond in the etching solution. The possible applications of the porous diamond will also be demonstrated.

Authors : P. Niedziałkowski1, R. Bogdanowicz2, P. Zięba1, A. Cirocka1, T. Ossowski1
Affiliations : 1Department of Analytical Chemistry, Faculty of Chemistry, University of Gdansk, Poland 2Department of Metrology and Optoelectronics, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, Poland

Resume : Nanocrystalline boron-doped diamond (B-NCD) electrodes have very interesting properties for electroanalysis. The detection of nucleobases and polynucleotides based on molecular recognition process can be performed on the B-NCD electrodes by immobilizing of organic molecules deposited directly on the electrode surface. This modification gives the possibility to obtain the electrochemical signals on a decent level of detection. Modification of B-NCD surface electrode by melamine gives the possibility of determining organic molecules such as: pyrimidines and purines. This modification mediates the oxidation process of nucleic acid bases enhancing charge transfer between the electrolyte and the electrode. This work describes electrochemical method of B-NCD surface modification by melamine to obtain organic film. Deposited in this way organic monolayer can be used to create biosensor for amperometric detection and determination selected nucleobases (e.g. thymine, guanine). The modification with melamine significantly increased the working potential range of the B-NCD electrodes compared to the unmodified electrodes. Cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) were used to characterize the obtained monolayer formed on the B-NCD electrode surface. The synthesis of polyamine layer on the B-NCD surface caused a significant broadening of the electrochemical window in both cathodic and anodic areas. Amperometric techniques were used for determination of the limit of detection and limit of quantification of different nucleobases on modified electrodes.

Authors : Johanna Svanberg-Larsson, Geoff W. Nelson, John S. Foord
Affiliations : University of Oxford, Department of Chemistry

Resume : Boron doped diamond (BDD) is an established commercial product in the field of electrochemistry, and is frequently employed in the area of electroanalysis. Diamond electrodes are often modified with active nanoparticles deposited on the electrode surface to change the electrochemical properties, for applications ranging from heavy metal sensing to biomedicine. Many methods have been used to achieve the decorated ensemble, although it is unclear which is the optimal deposition approach and what the effect of electrode termination (oxygen versus hydrogen, BDDO and BDDH, respectively) is on the subsequent electrochemical behaviour of the modified electrode. The aim of this project was to address these questions by comparing the characteristics of both BDDO and BDDH modified with gold nanoparticles (AuNPs) prepared by two different methods: electro-deposition and a colloidal, electroless deposition method. Their application for the electroanalytical detection of mercury was evaluated. The results obtained show that the dispersion and crystalline properties of the AuNPs on the diamond electrodes are strongly influenced by both the deposition method and the electrode termination. The electroanalytical performance was higher on BDDH than BDDO, regardless of the deposition method. For example, a limit of detection 16x better is seen on BDDH compared to BDDO for the detection of mercury. These results illustrate the importance of choosing an appropriate deposition method and controlling the electrode termination, when preparing modified diamond electrodes.

Authors : Paul W. May
Affiliations : School of Chemistry, University of Bristol

Resume : Diamond has a number of superlative properties that make it an excellent candidate for use in electrochemistry or electron emission applications. Key to these applications are a large surface area, and this can be achieved in diamond in various ways. Here we will show that coating vertically aligned carbon nanotube (CNT) forests with a thin layer of B-doped CVD diamond creates 'teepee' structures which increase the effective surface area of the diamond by 2 orders of magnitude. This greatly improves the sensitivity and capacitance of these composite structures when used as electrochemical electrodes. Denser CNT forests ave also been coated in diamond, leading to conducting honeycomb morphologies, again with very high active surface areas when used as electrodes. Field emission also depends strongly upon surface morphology. The teepees can also be used as electron sources in field emission devices greatly increasing the lifetime of field emissions devices. The basic mechanism of field emission from diamond films has been studied to determine whether the emission sites are the tips of protruding grains or grain boundaries. The new technique of PeakForce-tunnelling atomic force microscopy (PF-TUNA) has been used to directly image the electron emission sites from a variety of diamond films with varying grain size, morphology and doping (N, P or B). Remarkable high-resolution images demonstrate directly that emission primarily arises from grain boundaries.

12:30 Lunch Break    
Carbon Nanoparticles : John Foord
Authors : Marcin Opallo
Affiliations : Institute of Physical Chemistry, Polish Academy of Sciences, Warszawa, Poland

Resume : Our works on preparation, characterisation and applications of electrodes modified with phenyl sulphonated carbon nanoparticles and their derivatives will be reviewed. Such modification was done by adsorption of nanoparticles on electrode surface, their encapsulation in sol-gel processed functionalised film or by layer-by-layer technique. These electrodes exhibit electrocatalytic properties towards oxidation of some difficult to oxidise biologically important compounds and they were applied to selective and sensitive sensing of dopamine in both quiescent and microfluidic conditions and as element of self powered sensor of ascorbic acid. These carbon nanoparticles modified electrodes provide also good electronic communication with adsorbed redox enzymes as laccase, bilirubin oxidase, myoglobin, glucose oxidase and hydrogenase. Such electrodes were applied in biobatteries and biofuel cells. Finally electrochemical experiments in suspension of carbon nanoparticles will be also presented.

Authors : Keith Linehan, Darragh Carolan, Hugh Doyle
Affiliations : Tyndall National Institute, University College Cork, Lee Maltings, Cork, Ireland

Resume : Carbon quantum dots (CQDs) are attracting increasing interest due to their size-tuneable band gap, compatibility with solution processing, and tuneable surface chemistry. CQDs also possess advantages in terms of high luminescence efficiencies, chemical inertness and high resistance to photobleaching that make them appealing for applications including biological imaging, heavy metal ion sensing and electrogenerated chemiluminescence. Here the preparation and characterisation of size monodisperse CQDs synthesised in reverse micelles is demonstrated using a simple room temperature, solution-phase synthesis. Regulation of the quantum dot size is between 2 to 6 nm is achieved by selection of the surfactant used to form the inverse micelles or the strength of the reducing agent. The use of micelle templates allows for control over the CQDs size, while covalently bound capping molecules (ligands) chemically passivate the CQD surface to prevent oxidation. Varying the capping ligands allowed the CQDs to be dispersed in either hydrophobic or hydrophilic solvents. The CQDs possess a high photoluminescence quantum yield (25 %), strong blue emission with a marked dependency on excitation wavelength and excellent photostability. CQDs were stable under ambient atmospheric and lighting conditions over a period of months, with little change in surface oxidation levels over time, as verified by FTIR and XPS.

Authors : F. Ehrat1, 2, M. Fu1, 2, Y. Wang3, C. Reckmeier,3 J. K. Stolarczyk1, 2, A. L. Rogach3, A.S. Urban1, 2, *, J. Feldmann1, 2
Affiliations : 1 Photonics and Optoelectronics Group, Department of Physics and Center of NanoScience (CeNS), Ludwig-Maximilians-Universität (LMU), Munich, Germany 2Nanosystems Initiative Munich (NIM), Schellingstr. 4, 80799 Munich, Germany 3 Department of Physics and Materials Science and Centre for Functional Photonics (CFP), City University of Hong Kong, Hong Kong SAR

Resume : Carbon dots (CDs) have attracted rapidly growing interest due to their exceptional advantages such as high fluorescence quantum yield, chemical stability, biocompatibility, and low toxicity. [1,2] However, due to the complex structure of CDs, the intrinsic mechanism and origin of the fluorescence in CDs have not yet been completely understood. We have recently developed a model system of polycyclic aromatic hydrocarbon molecules embedded in a polymer matrix to reproduce the optical properties of CDs.[3] We showed that the large Stokes shift (>100nm) as well as excitation wavelength dependent emission properties could be achieved by fine-tuning of the concentration of only three molecules, anthracene, pyrene and perylene. Furthermore, using excitation-dependent time-resolved photoluminescence measurements, we provide insights into the energy transfer and exciton relaxation mechanism within the CDs. These results will help to tailor the optical properties of CDs for applications in light-emitting devices, photocatalysis and lasing. References: [1] S. Zhu, Q. Meng, L. Wang, J. Zhang, Y. Song, H. Jin, K. Zhang, H. Sun, H. Wang, B. Yang, Angew. Chem. Int. Ed. 2013, 52, 3953–3957. [2] Y. Wang, S. Kalytchuk, Y. Zhang, H. Shi, S. V. Kershaw, A. L. Rogach, J. Phys. Chem. Lett. 2014, 5, 1412−1420 [3] M. Fu, F. Ehrat, Y. Wang, K. Z. Milowska, C. Reckmeier, A. L. Rogach, J. K. Stolarczyk, A. S. Urban, J. Feldmann, manuscript submitted

Authors : Bao-Ping Qi, Dai-Wen Pang*
Affiliations : Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, State Key Laboratory of Virology, The Institute for Advanced Studies, and Wuhan Institute of Biotechnology, Wuhan University, Wuhan, 430072, P. R. China

Resume : The abundant oxygenic groups, such as -COOH, -OH, -C-O-C-, -C=O, on graphene quantum dots (GQDs) will be in favour of its functionalization. However, the oxygenic group of ortho-quinone structures characteristic of high activity has been rarely reported. Especially, the direct evidence regarding ortho-quinone structures at the edge of GQDs is needed. By adopting electrochemical method to study GQDs, a pair of reversible redox peaks with a formal potential at 0.29 V and an irreversible oxidation peak can be detected in phosphate buffer solution (PBS). A pair of symmetrical redox peaks could be attributed to peripheral functional moieties at the edge of GQDs that are analogous to ortho-quinone derivatives. As oxidation degree during the preparation of GQDs increased, the ortho-quinone structures would be damaged to a large extent. The moderate oxidation conditions are beneficial to production of ortho-quinone structures. Based on the high specificity of the acid-catalyzed dehydration reaction between ortho-quinones and 1,2-diamines, an efficient route via such a convenient reaction has been developed to modulate photoluminescence emissions of GQDs in our group.

15:30 Coffee Break    
Carbon Composite : Xin Jiang
Authors : Ieva Kranauskaite 1, Jan Macutkevic 1, Juras Banys 1, Vladimir L. Kuznetsov 2, Sergey I. Moseenkov 2
Affiliations : 1 - Department of Radiophysics, Vilnius University, Vilnius, Lithuania 2 - Boreskov institute of Catalysis SB RAS, Novosibirsk, Russia

Resume : Dielectric properties of carbon nanotubes (CNT) composites were investigated very often, mainly in order to find an electrical percolation. However, the relation between CNT microscopic parameters (like length or diameter), CNT preparation technique, polymer matrix parameters and percolation threshold in composites up to now is not clear [1]. Therefore, before experiment it rather impossible to predict dielectric properties of CNT composites. Generally, it expected that percolation threshold is directly proportional to CNT length/diameter aspect ratio, however this relation experimentally was never observed and more complicated formula were used in order to establish influence of aspect ratio on percolation threshold in composites. In this presentation results of dielectric investigations of Polymethylmethacrylate (PMMA) matrix composites filled with multiwalled carbon nanotubes (MWCNT) will be presented and discussed in wide frequency (20 Hz - 3 THz) and temperature (30 K – 450 K) range. This research is supported by European Social Fund under Global Grand Fund. [1] W. Bauhofer, J. Z. Kovacs, A review and analysis of electrical percolation in carbon nanotube polymer composite, Composite Science and Technology 69, 1486 (2009).

Authors : A.Mukhtarov, S.Usmanova, S.Kalandarova, H.Akbarov
Affiliations : National university of Uzbekistan, Institute of nuclear physics of Uzbekistan Academy of Sciences

Resume : Carbon and silicon nanotubes are unique hydrogen-accumulating and transport systems. But the desorption of hydrogen from nanotubes is problematic. Influence of various external factors on the strength of hydrogen bonding with the lattice will help you find ways to release hydrogen from nanotubes. These external factors are the charge state of the tubes, mechanical force and others. In this study, we investigated the phenomenon of hydrogen bonding in carbon and silicon nanotubes and the study of microscopic factors on the binding energy of hydrogen in nanotubes by computer simulation an nonconventional tight-binding method and molecular dynamics. Our results show that the carbon nanotube binds weakly hydrogen molecule compared to a silicon tube. Zigzag-type nanotubes tightly connected with the hydrogen spiral tube least active. Increasing tube diameter reduces the hydrogen bonding. Among the structural lattice distortions, open position most strongly binds hydrogen bend tube has minimal value and the smallest value pentagon bond energy Si-H. The excess negative charge weakens the connection wall and the H2 molecule. Giving negative charge of the nanotube, it can be distinguished from the hydrogen gas.

Authors : Chiara Pintossi (1), Stefano Ponzoni (1), Giovanni Drera (1), Stefania Pagliara (1), Francesco De Nicola (2), Maurizio De Crescenzi (2), Paola Castrucci (2), Luigi Sangaletti (1)
Affiliations : (1) Interdisciplinary Laboratories for Advanced Materials Physics (i-LAMP), Dipartimento di Matematica e Fisica, Università Cattolica del Sacro Cuore, Brescia, Italy. (2) Dipartimento di Fisica, Università degli Studi di Roma Tor Vergata, Rome, Italy.

Resume : In last ten years, hybrid devices based on junctions between single-walled carbon nanotube (SWCNT) and silicon had proved to be one of the most valid alternative to conventional silicon solar cells. Among various open issues, one of the most compelling concerns the device operation mechanism. In fact, by investigating these devices through X-ray photoelectron spectroscopy, a complex SiOx interface has been identified and its role in the device behavior need to be clarified. By removing all the oxides at the interface level using hydrofluoric acid (HF) vapors, it has been possible to evaluate the SiOx effect on the device operation, which revealed to depend on the geometry of the CNT thin film on top. In particular, devices with horizontally aligned SWCNT display higher efficiency without oxides, indicating that their behavior is similar to a conventional p-n junction. On the other hand, for devices made up with randomly aligned SWCNT, the behavior is not so trivial. By combining different experimental techniques, such as XPS, time resolved reflectivity, Raman spectroscopy and the J-V tracking, we have been able to unambiguously prove that this complex oxide layer need to reach an optimal thickness in order to have the best performances. This complex behavior allowed us to conclude that, in the case of randomly aligned SWCNT, the device can be modeled as a metal-insulator-semiconductor (MIS) junction.

Authors : Hao Zhuang, Nianjun Yang*, Lei Zhang, Regina Fuchs, Xin Jiang*
Affiliations : Institute of Materials Engineering, University of Siegen, 57076 Siegen, Germany

Resume : Silicon carbide (SiC), a wide band gap material, has been considered for many different applications such as for powder devices. Due to its rich surface properties and the possibility to be functionalized, SiC has been paid attention recently for electrochemical and biochemical applications. In this presentation, we will show the growth and properties of nanocrystalline, microcrystalline and epitaxial (001) 3C-SiC films using microwave plasma chemical vapor deposition technique under different conditions. Especially electrochemical properties of these films will be shown in detail, regarding electrochemical potential windows, capacitance, redox activities. Based on these properties, the applications of different SiC films as dopamine electrochemical sensor and electrochemical capacitor will be summarized. Further surface functionalization of SiC for DNA biosensing will be outlined as well.

Authors : Xiaoning Guo,* Xili Tong, Xiangyun Guo
Affiliations : State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan, 030001, PR China.

Resume : Fisher-Tropsch synthesis (FTS) converts carbon monoxide and hydrogen to liquid fuels and chemicals and is usually operated under high temperature ranges, which results in an evident energy consumption and CO2 emission. A photocatalytic FTS route was proposed to efficiently harvest solar energy. Worm-like ruthenium nanostructures dispersed on graphene sheets can effectively catalyze FTS at mild conditions under irradition of visible light and achieve a catalytic activity as high as 14.4 molcomolRu-1h-1.The reaction rate of FTS can be enhanced by increasing the irradiation tensity of decreasing the irradiation wavelength . The work provides a green and efficient photocatalytic route for FTS.

17:15 Close of the symposium    
Start atSubject View AllNum.
18:00 Best Student Presentation Awards Ceremony and Reception (Main Hall)    

No abstract for this day

Symposium organizers
Nianjun YANGUniversity of Siegen

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

+49 2717402531
Chunhai FAN Shanghai Institute of Applied Physics, CAS

Shanghai 201800 China

+86 2139194129
John S. FOORDUniversity of Oxford

OX1 3TA, UK.

+44 1865 275967
Greg M. SWAINMichigan State University

East Lansing, MI 48824-1322 USA

+1 517 3559715229
Yasuaki EINAGAKeio University

Yokohama 223-8522 Japan

+81 455661704