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Full-Text Articles in Physical Sciences and Mathematics
Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals, Hai-Bin Wu, Rui-Zhong Zhang, Wei Chen
Synthesis And Electrocatalysis Of Pdcu Alloy Nanocrystals, Hai-Bin Wu, Rui-Zhong Zhang, Wei Chen
Journal of Electrochemistry
Monodispersed PdCu alloy nanoparticles were synthesized by co-reduction of Cu(acac)2 and Pd(acac)2 with 1, 2-hexadecanediol. The spherical and popcorn-like shapes of PdCu alloy nanoparticles were obtained by changing the ratios of mixed surface protecting ligands of 1-octadecene, and oleylamine or oleic acid. TEM and XRD measurements showed that both PdCu nanoparticles are alloy nanocrystals dominated with (111) planes and the average sizes are 12.7 ± 0.18 and 20.4 ± 0.31 nm for he spherical and popcorn-like PdCu nanoparticles, respectively. The electrocatalytic activities of the PdCu nanocrystals for formic acid oxidation were evaluated by electrochemical cyclic voltammetry (CV). The result showed …
Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst, Ming-Xuan Li, Jie-Lian Ou, Sheng-Pei Chen, Peng Wang, Bin-Bin Xu, Shi-Gang Sun
Preparation And Catalytic Properties Of Feco Alloy Nanocatalyst, Ming-Xuan Li, Jie-Lian Ou, Sheng-Pei Chen, Peng Wang, Bin-Bin Xu, Shi-Gang Sun
Journal of Electrochemistry
The FeCo alloy nanoparticles were electrodeposited on glassy carbon electrode by chronoamperometry and were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results showed that the shapes of FeCo nanoparticles were cubes with an average size of 65 nm. The atom ratio of Fe and Co is 1:1. As indicated from the pattern of selected area electron diffraction (SAED), the FeCo cubic nanoparticles were single crystal which belonged to body-centered cubic with an interval of 0.201 nm referring to the (110) facets of FeCo alloy. The FeCo cubic nanoparticles exhibited the enhanced electrocatalytic …
An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2c/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen
An In Situ Ftir Spectroelectrochemical Study On Methanol Oxidation At Pt-Mo2c/Gc Catalyst, Hai-Ping Huang, Xi-Yu Yao, Pei-Kang Shen
Journal of Electrochemistry
A 40% Pt on Mo2C/GC catalyst has been prepared by ion exchange method. The mechanism of methanol electrooxidation on Pt-Mo2C/GC and commercial Pt/C catalysts in acidic media was studied by cyclic voltammetry, XRD measurements and in-situ Fourier transform infrared spectroelectrochemistry. The results revealed that the Pt nanoparticles were uniformly dispersed on Mo2C/GC with an average particle size of 3 nm. The cyclic voltammetric and chronopotentiometric experiments indicated that Pt-Mo2C/GC catalyst exhibited a better performance for methanol oxidation than that of Pt/C in acid solution. A negative shift over 90 mV of the onset potential for methanol oxidation was found on …
Electrocatalytic Oxidation Of Formic Acid On Pd/Ni Heterostructured Catalyst, Mingjun Ren, Liangliang Zou, Ju Chen, Ting Yuan, Qinghong Huang, Haifeng Zhang, Hui Yang, Songlin Feng
Electrocatalytic Oxidation Of Formic Acid On Pd/Ni Heterostructured Catalyst, Mingjun Ren, Liangliang Zou, Ju Chen, Ting Yuan, Qinghong Huang, Haifeng Zhang, Hui Yang, Songlin Feng
Journal of Electrochemistry
A Pd/Ni bimetallic nanostructured electrocatalyst was fabricated via a two-step reduction route. Owing to an epitaxial growth of Pd atoms on the surface of Ni nanoparticles, heterostructured Pd/Ni nanocomposites were formed and verified by high resolution transmission electron microscopy combined with energy-dispersion X-ray spectroscopy. X-ray diffraction confirmed that the as-prepared Pd/Ni nanocomposites possessed a single face-centered-cubic (fcc) Pd structure, probably due to a weaker diffraction intensity of metallic Ni and/or overlapping by that of Pd. The intrinsic catalytic activity on the Pd/Ni is higher than that on the Pd. Moreover, the durability of formic acid oxidation on the Pd/Ni was …
Electrochemical Properties Of The Keggin-Type Lacunary Heteropolysilicate Anion And Its Eectrocatalysis For H2o2 Reduction, Xi-Long Liu, Chun-Yan Wu, Fang Zhou, Hong-Sheng Liu, Ying-Jie Hua, Chong-Tai Wang, Xiao-Yang Liu
Electrochemical Properties Of The Keggin-Type Lacunary Heteropolysilicate Anion And Its Eectrocatalysis For H2o2 Reduction, Xi-Long Liu, Chun-Yan Wu, Fang Zhou, Hong-Sheng Liu, Ying-Jie Hua, Chong-Tai Wang, Xiao-Yang Liu
Journal of Electrochemistry
Electrochemical properties of the Keggin-type lacunary heteropolysilicate anion SiW11O398- (SiW11) and its indirect electrocatalysis for H2O2 reduction in the supporting electrolyte containing 0.1 mol?L-1 NaHSO4 and Na2SO4 solutions were investigated using cyclic voltammetry, square wave voltammetry and alternating current impedance spectroscopy. Experimental results indicated that SiW11 showed two pairs of reversible redox waves on the glassy carbon (GC) electrode in an acidic solution. The electron transfer number corresponding to the two pairs of waves was one, and the proton transfer number involved was two during the electrode reaction. The diffusion coefficient (D0) of SiW11 calculated from the linear relationship of …
Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng
Electrocatalytic Oxidation Of Hydrazine At Rutin Carbon Nanotubes Modified Electrode, Hong-Fang Zhang, Qing-Lin Sheng, Jian-Bin Zheng
Journal of Electrochemistry
The electrochemical behavior and electrocatalytic oxidation of hydrazine on rutin multiwall carbon nanotubes modified glassy carbon electrode were studied by cyclic voltammetry.The experimental results indicated that the electrode exhibits good electrocatalytic activity to hydrazine at a reduced oxidation potential of 262 mV.The amperometric response of the modified electrode showed linear increase after successive addition of hydrazine in the concentration range of 2.5×10-6~1.0×10-4 mol·L-1 with a detection limit of 5×10-7 mol·L-1.
Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng
Electrooxidation Of Methanol On Multilayer Films Of Polypyrrole-Platinum Electrode, Ling Zhang, Long-Zhen Zheng
Journal of Electrochemistry
Multilayer films of polypyrrole-platinum electrode were fabricated by cyclic voltammetric technique.Electro-oxidation of methanol on this electrode was investigated with the aid of cyclic voltammetry and chronoamperometry.Results demonstrated that the multilayer of polypyrrole-platinum electrode behaved better electrocatalytic performance for electro-oxidaton of methanol and better poison resistant.Furthermore,with the increase of deposited platinum loadings,the rate controlling step on electro-oxidation reaction of methanol was changed from CO oxidation to sorption-desorption of hydrogen.
Comparative Study Of Nanoporous Pt,Ptru And Ptruir Catalysts Using Electrochemical Ftir Spectroscopy, M. Amussen Robert, Holt-Hindle Peter, Nigro Samantha, Chen Aicheng
Comparative Study Of Nanoporous Pt,Ptru And Ptruir Catalysts Using Electrochemical Ftir Spectroscopy, M. Amussen Robert, Holt-Hindle Peter, Nigro Samantha, Chen Aicheng
Journal of Electrochemistry
In recent years much effort has been put towards developing efficient Pt-based electrocatalysts for applications in fuel cells. With the rising cost of precious metals such as Pt,the need to enhance the activity and to decrease the load of catalysts is prominent. Herein we report on the synthesis and comparative study of nanoporous Pt,PtRu and PtRuIr electrocatalysts. The nanoporous electrodes were fabricated using a hydrothermal method and characterized by scanning electron microscopy (SEM) ,energy dispersive spectroscopy (EDS) ,X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) . The electrocatalytic activity of the fabricated nanopo- rous materials was evaluated using both CO …
An In Situ Fourier Transform Infrared Spectroelectrochemical Study On Alcohols Electrocatalytic Oxidation At Pd Electrode In Acidic Solution, Hai-Ping Huang, Lian-Qin Wang, Pei-Kang Shen
An In Situ Fourier Transform Infrared Spectroelectrochemical Study On Alcohols Electrocatalytic Oxidation At Pd Electrode In Acidic Solution, Hai-Ping Huang, Lian-Qin Wang, Pei-Kang Shen
Journal of Electrochemistry
The methanol and ethylene glycol electrooxidation on palladium electrode in acidic solution has been investigated by cyclic voltammetry and in situ Fourier transform infrared spectroelectrochemistry. It shows that the oxidation of methanol and ethylene glycol at Pd electrode cannot proceed until over 1. 5 V in acidic and neutral media. The overpotential decreases and the peak current density increases with the reduction in pH values. The formation of the oxygen-containing species significantly affects the alcohol oxidation on Pd electrode. The in situ FTIR spectroscopic measurements show that the oxidation products of ethylene glycol on Pd electrode are CO2 and oxalic …
Electrocatalytic Oxidation Of Hcooh At Au_(Core)-Pd_(Shell)-Pt_(Cluster) Nanocubes, Qing-Ning Jiang, Huan Li, Ning Yang, Ping-Ping Fang, Feng-Ru Fan, Zhong-Qun Tian
Electrocatalytic Oxidation Of Hcooh At Au_(Core)-Pd_(Shell)-Pt_(Cluster) Nanocubes, Qing-Ning Jiang, Huan Li, Ning Yang, Ping-Ping Fang, Feng-Ru Fan, Zhong-Qun Tian
Journal of Electrochemistry
Gold nanocubes were synthesized by a two-step seed-mediated growth method. The Aucore-Pdshell and Aucore-Pdshell-Ptcluster nanocubes with controllable shell thickness of Pd and cluster coverage of Pt were synthesized by simply changing the amount ratio of H2PdCl4 or H2PtCl6. The samples were characterized by scanning electron microscope ( SEM) 、transmission electron microscopc ( TEM) and cyclic voltammetry ( CV) . CV was then used to make a systematic study on the dependence of the electrocatalytic properties on the shell thickness of Aucore-Pdshell and Pt coverage of Aucore-Pdshell-Ptcluster,respectively. The results indicated that the Au nanocube core coated by three atomic layers of …
Synthesis Of Cosalen Composite In Apo-5 And Its Electrocatalytic Behaviour For Reaction Of Dioxygen Reduction, Rong Zhang, Li-Hua Tang, Bin-Bin Fan, Jing-Hong Ma, Rui-Feng Li
Synthesis Of Cosalen Composite In Apo-5 And Its Electrocatalytic Behaviour For Reaction Of Dioxygen Reduction, Rong Zhang, Li-Hua Tang, Bin-Bin Fan, Jing-Hong Ma, Rui-Feng Li
Journal of Electrochemistry
CoAPO-5 molecular sieve was hydrothermally synthesized. The Cobalt ions in CoAPO-5 were coordinated with the SALEN ligend diffusing into the channels of the molecular sieve to form CoSALEN complexes. The electrochemical behaviors and electrocatalysis for dioxygen reduction of the CoSALEN complex immobilized in APO-5 modified glassy carbon electrodes ( GCEs) have been investigated by cyclic voltammetry( CV) and chronoamperometry ( CA) in differrent pH aqueous solutions. The results showed that the PS/CoSALEN/APO-5 /GC modified electrode is of the high electrocatalytic activity towards dioxygen reduction in pH 6. 86 buffer solution with a reduced overpotential of 447 mV lower than bare …
Electrooxidation Of Formic Acid On Pd-Ni Alloy Film Electrode-The Effect Of Dealloying, Chao Wang, Fei-Fei Shi, Jin-Yi Wang, Han-Xuan Zhang, Wen-Bin Cai
Electrooxidation Of Formic Acid On Pd-Ni Alloy Film Electrode-The Effect Of Dealloying, Chao Wang, Fei-Fei Shi, Jin-Yi Wang, Han-Xuan Zhang, Wen-Bin Cai
Journal of Electrochemistry
A Pd-Ni alloy film was electrodeposited on Au disc electrode at a constant potential from a weakly basic bath containing PdCl2,NiSO4 and ethylenediamine.The as-deposited film was then subjected to potential cycling in a perchloric acid solution for surface dealloying treatment.The dealloyed Pd-Ni film electrode was examined for the electrocatalytic oxidation of formic acid,and compared with the as-deposited one as well as a Pd film electrode.The FE-SEM and electrochemical measurements on the Pd-Ni films revealed that the dealloying treatment caused a surface roughening and an increase in specific surface reaction area.The ICP-AES and XPS analyses demonstrated that the preferential dissolution of …
Electrocatalysis In Polymer Electrolyte Membrane Fuel Cells, Li Li, Si-Guo Chen, Xue-Qiang Qi, Yao-Qiong Wang, Meng-Bo Ji, Lan-Lan Li, Zi-Dong Wei
Electrocatalysis In Polymer Electrolyte Membrane Fuel Cells, Li Li, Si-Guo Chen, Xue-Qiang Qi, Yao-Qiong Wang, Meng-Bo Ji, Lan-Lan Li, Zi-Dong Wei
Journal of Electrochemistry
This review presents the study of Chongqing University in electrocatalysis for polymer electrolyte membrane fuel cells(PEMFCs).Based on the understanding to the performance degradation of PEMFCs' catalysts,the university has being concentrated on how to increase the activity,stability and utility of noble metal catalysts.It covers the molecular design of near-surface alloy catalysts for improvement of activity to oxygen reduction reaction(ORR) and resistance to foreign poison species,selective deposition of Pt on the so-called "three-phase interface" for a high Pt utility,and invention of anti-flooding electrode against water flooding in the catalyst layer of the membrane assemble electrode(MEA),and so on.The catalytic mechanism of electrode reactions …
Direct Electrochemistry Of Chloroperoxidase At Gc Electrode Modified With Swnts, Hong-Xia Zhang, Xia-Qin Wu, Wen-Jing Hou, Wen Xie, Zhong-Qing Lu, Rong Wang, He-Xing Li
Direct Electrochemistry Of Chloroperoxidase At Gc Electrode Modified With Swnts, Hong-Xia Zhang, Xia-Qin Wu, Wen-Jing Hou, Wen Xie, Zhong-Qing Lu, Rong Wang, He-Xing Li
Journal of Electrochemistry
The chloroperoxidase(CPO) was immobilized onto the surface of SWNTs modified electrodes.The electrochemical behaviors of modified electrode have been investigated by cyclic voltammetry.The appearance of a pair of well-defined redox peaks in the CV curve indicated that SWNTs can promote the electron transfer reaction of CPO.The results of cyclic voltammetry in PBS of different pH,from 3~9,showed that the reaction of CPO on the modified electrode was with equal numbers of electron and protein.This readily prepared SWNTs modified electrode showed excellent stability and good catalysis to O2.
Voltammetric Determination Of L-Cysteine At Bipyrine Bridged Copper(Ⅱ) Complex Modified Glassy Carbon Electrode, Ming-Yan Wang, Fan Yang, Sheng-Yu Zhang, Xing-You Xu, Xu-Jie Yang
Voltammetric Determination Of L-Cysteine At Bipyrine Bridged Copper(Ⅱ) Complex Modified Glassy Carbon Electrode, Ming-Yan Wang, Fan Yang, Sheng-Yu Zhang, Xing-You Xu, Xu-Jie Yang
Journal of Electrochemistry
A modified electrode has been constructed by depositing a novel copper(Ⅱ) complex 2biPy(ClO4)4 on the glassy carbon electrode through the method of cyclic voltammetry(CV).It was found that the modified electrode exhibited high electrocatalytic activity toward L-Cysteine oxidation with good reproducibility and high sensitivity.The peak current of semi-derivative linear scan was proportional to the concentration of L-cys in the range of 1×10-6～3×10-4 mol·L-1.The detection limit was 5×10-7 mol·L-1.
Design And Fabrication Of The High Efficient Platinum-Nanoporous Gold Catalysts, Zhao-Na Liu, Jin-Tao Zhang, Fang Tian, Peng-Peng Liu, Hou-Yi Ma, Yi Ding
Design And Fabrication Of The High Efficient Platinum-Nanoporous Gold Catalysts, Zhao-Na Liu, Jin-Tao Zhang, Fang Tian, Peng-Peng Liu, Hou-Yi Ma, Yi Ding
Journal of Electrochemistry
The nanoporous gold(NPG) electrodes with uniform pore sizes and ligaments were prepared by using a simple dealloying method.The as-prepared NPG showed high catalytic activity towards the oxidation of formic acid and formaldehyde.After tiny amount of platinum was deposited onto the NPG substrate,not only the structure stability of NPG was greatly improved,but also the Pt-Au bimetallic catalysts displayed the better catalytic activity and the stronger poison resistance towards the electrooxidation of small organic molecules than the bulk platinum due to synergistic effect between Au and Pt compositions.
Electrochemical Studies On Electrocatalytic Activity Of Au_(Core) Pt_(Shell)Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu
Electrochemical Studies On Electrocatalytic Activity Of Au_(Core) Pt_(Shell)Nanoparticles To Methanol Oxidation, Fang Bao, Jian-Lin Yao, Ren-Ao Gu
Journal of Electrochemistry
Au_(core)Pt_(shell)nanoparticles with different thicknesses were prepared by using chemical reduction method,and characterized by ultraviolet-visible spectroscopy(UV-Vis),transmission electron microscopy(TEM) and cyclic voltammetry(CV).The electrocatalytic activity of Au_(core)Pt_(shell)nanoparticles with the mean diameter of 70~80 nm to methanol oxidation was investigated by cyclic voltammetry in the acid solution.The results revealed that the prepared core-shell nanoparticles were covered by Pt shell and exhibited the similar optical property and electrocatalytic activity with the normal Pt surface.Moreover,the electrocatalytic activity increased with the electrochemical sweep in the certain potential range.It might be contributed by the special loose structure of Pt shell rather than the increase of the real area.
Electrocatalytic Oxidation Of Glucose On Nano Pt/C Electrode, Cui-Lian Chen
Electrocatalytic Oxidation Of Glucose On Nano Pt/C Electrode, Cui-Lian Chen
Journal of Electrochemistry
Nano Pt/C electrocatalysts were prepared by intermittent microwave heating method.The electrooxidation of glucose on smooth Pt and～Pt/C electrodes has been studied and compared.The results showed that the electrochemical properties on nano Pt/C were improved due to the reduction of the overpotential and the increase in the kinetic rate.The surface area would be significantly increased when the particle size of the catalyst was reduced to nano-scale,resulting in the increase in the activity.The enhancement in the resistance to poisoning could be explained that the oxygen-containing species are easier to react with poisoning species on nano Pt/C and re-active the electrode.
Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu
Adual-Celltechnique And Its Application In Electrocatalytic Study Of Pt-Ru Metals, Lei Su, Bing-Liang Wu
Journal of Electrochemistry
Two local electrochemical reactive interfaces are established using two strips of Nafion~ membrane separated each other, which are in contact with different surface regions of the same metal-sheet working electrode. One potentiostatis used to control thepotentialof one electrochemical reactive interface to generate adsorbed surface speciesand the other potentiostatto hold the potential of the second interface as a detector of the intermediate. The adsorbed surface species driven by the difference in surface concentration diffuses alongthe surface of the metal-sheet between both local electrochemical interfaces and can be detected at the second interface when they achieveover there.The surface diffusion coefficient of the …
Solid State Synthesis And Electrocatalysis Of Pt/Moo_3 For The Oxidation Of Methanol, Wang Qing
Solid State Synthesis And Electrocatalysis Of Pt/Moo_3 For The Oxidation Of Methanol, Wang Qing
Journal of Electrochemistry
The electrocatalyst, Pt/MoO_(3) synthesized by solid state reaction, was used for the oxidation of methanol in direct methanol fuel cells. The X-Ray diffraction and cyclic voltammetry were employed to investigate the performance of the material. It was shown that the typical diffraction peaks for Pt appeared in XRD. And a good electrocatalysis for methanol oxidation was observed. The peak potential of the methanol oxidation appeared at ca. 0.63V(vs.SCE) and the peak current density for the oxidation was 78.1 mA cm~(-2) .
The Mechanism Of Electrocatalytic Reduction Of Oxygen On Manganese Dioxide, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai, Li-Fen Xiao
The Mechanism Of Electrocatalytic Reduction Of Oxygen On Manganese Dioxide, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai, Li-Fen Xiao
Journal of Electrochemistry
The oxygen electroreduction on the MnO 2 electrode was investigated by analysis of the polarzation properties of oxygen reduciton and its dependence on MnO 2 discharge state,in combination with the characterization of discharge intermediate and the kinetic parameters of the oxygen reduction.Based on the experimental observation and mechanistic analysis,it was suggested that the reduction of oxygen was closely related to the discharge behaviors of MnO 2 .When MnO 2 was electrochimically reduced to MnOOH,it was immediately oxidized by oxygen molecules. Thus the oxygen reduction proceeds through continuous oxidation of the discharge product of MnO 2 and the MnO 2 catalyst …
Electrochemistry And Electrocatalysis Of A Novel Μ-Oxamido Copper(Ⅱ) Binuclear Complex, Gui-Lian Gao, Guo-Bao Li, Qiu-Xia Yang, Xue-Lin Wang
Electrochemistry And Electrocatalysis Of A Novel Μ-Oxamido Copper(Ⅱ) Binuclear Complex, Gui-Lian Gao, Guo-Bao Li, Qiu-Xia Yang, Xue-Lin Wang
Journal of Electrochemistry
In this paper,the cyclic voltammetric and spectroelectrochemical behaviors of μ _oxamido Copper(Ⅱ) Binuclear Complex (deCu) in PBS were studied.Cyclic voltammograms of this complex in PBS(pH=9)exhibited two reductive peaks( E pc1 =-0.25 V, E pc2 =-0.50 V)at hanging mercury drop electrode(HMDE),peaks at -0.50 V and -0.25 V corresponded to the reduction of ligand and copper(Ⅱ)_complex, respectively.The spectroelectrochimical experiments showed that there was a new absorption band at 440 nm,and the absorption peaks at 270 nm,280 nm red shifted to 300 nm,310 nm under potential of -0.75 V.It was meant that the Cu(Ⅱ) turned into low valent copper,simultaneously,a new large coupling system …