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Progresses In Electrocatalysis Of Nanomaterials—Tuning The Surface Structure And Property Of Electrocatalysts, Yan-Xia Jiang, Na Tian, Zhi-You Zhou, Sheng-Pei Chen, Shi-Gang Sun

Journal of Electrochemistry

The property of an electrocatalyst depends strongly on its surface structure.The study of surface structure-catalytic functionality is the base of design and preparation of electrocatalysts of high activity,high stability and high selectivity at microstructure level.In this paper,based mainly on our results concering hydrogen and oxygen adsorption-desorption,ethylene glycol oxidation and CO₂ reduction,the research progresses in tuning the surface structure and property of electrocatalysts are summarized.This paper overviews firstly the cyclic voltammetric characteristics,electrocatalytic properties of platinum single crystal planes lying on different crystallographic zones of the unit stereographic triangle of face-centered cubic(fcc) metals.Next,the innovation of electrochemical methods to control the surface …

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 …

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 …

Highly Durable Pt/Ruo2/C Catalyst For The Cathode Of Direct Methanol Fuel Cells, Chun-Yu Du, Tao Dong, Ge-Ping Yin, Peng-Fei Shi

Journal of Electrochemistry

Instability of the carbon-supported Pt(Pt/C) catalyst at the cathode is one of the key technical challenges for the development of Direct Methanol Fuel Cells(DMFCs).In this paper,an efficient approach to enhancing the stability of the cathode catalyst was explored by designing and synthesizing a novel nanocomposite support,RuO₂ coated carbon black(RuO₂/C).Firstly,a wet chemical method was employed to synthesize the RuO₂/C nanocomposite,from which Pt/RuO₂/C catalyst was further prepared by a microwave method.The morphology and crystalline structure of the RuO₂/C support and Pt/RuO₂/C catalyst were then characterized by TEM and XRD.Finally,the electrochemical performance …

Synthesis And Electrocatalytic Properties Of Ni-Pd/C Catalysts With Pd-Enriched Surface, Yu-Mei Chen, Zhi-Xiu Liang, Sheng-Li Chen

Journal of Electrochemistry

The Ni-Pd alloy catalysts with Pd-enriched surface were synthesized through a modified polyol process.The synthesized materials were investigated by XRD and electrochemical methods,and tested as electrocatalysts for CH₃OH-tolerant oxygen reduction.The results indicated that the synthesized Ni-Pd nanoparticles possess multiple phases containing Pd-Ni alloy and pure Ni.Comparing with Pd/C,the prepared Ni-Pd/C nanoparticles exhibited better resolved voltammetric peaks between the hydrogen absorption and adsorption,and positively shifted current peaks for the reduction of Pd oxide.The prepared Ni-Pd alloys with Pd-enriched surface have significantly enhanced ORR activity and improved CH₃OH tolerance as comparing with Pd/C catalysts.

Complex Reduction Preparation Of Carbon Supported Pd Nanoparticle Catalyst And Its Electrocatalysis For Formic Acid Oxidation, Wei He, Yong-Yin Kang, Chong Du, Zhi-Qing Zou, Xiao-Gang Zhang, Hui Yang

Journal of Electrochemistry

A simple procedure involved the complexing of PdCl₂ with sodium citrate followed by ethylene glycol reduction has been employed for the preparation of carbon-supported Pd nanoparticles(Pd/C).The XRD and TEM characterizations indicate that Pd nanoparticles with a small particle size were well-dispersed on carbon support.The mean particle sizes of the Pd/C catalysts were found to be increased from 2.7 to 5.8 nm with heat-treatments at different temperature.The mass activity of the Pd/C catalyst for formic acid electrooxidation increased with the decrease in Pd particle size.However,the specific activity increased with Pd particle size.Furthermore,the Pd/C catalyst with a particle size of ca.3.6 …

Electrocatalytic Performance Of Carbon Supported Ir Catalysts With Different Ir Loadings For Ammonia Oxidation, Yu-Zhi Jiang, Qing-Mei Kong, Tian-Hong Lu, Yi-Ming Zhou, Ya-Wen Tang

Journal of Electrochemistry

The electrocatalytic performance of the Ir/C catalyst as the anodic catalyst in the amperometric and electrochemical NH₃ sensor was investigated.The experimental results illustrated that in the NaClO₄ neutral electrolyte,the electrocatalytic performance of the Ir/C catalyst for the NH₃ oxidation is related to the Ir loading in the Ir/C catalyst.Among the Ir/C catalysts with different Ir loading,the best electrocatalytic activity,stability and sensitivity were achieved by the Ir/C catalyst with 10% Ir loadings.In addition,the current densities of the NH₃ oxidation at the Ir/C catalysts with the different Ir loadings were linearly proportional to the NH₃ concentration.The Ir/C …

Cyclic Voltammetric And In-Situ Ftir Spectroscopic Studies Of Adsorption And Reduction Of No On Electrode Of Pt Nanoparticles, Qian Cheng, Yan-Xia Jiang, Dong-Mei Zeng, Shi-Gang Sun

Journal of Electrochemistry

Adsorption and reduction of NO on electrode of Pt nanoparticles in acid solutions were studied by means of cyclic voltammetry(CV) and in-situ FTIR spectroscopy.The results indicated that the reduction of NO is a complicated process including the adsorption of NO on electrode surface.Two types of surface-bonded NO were determined on Pt nanoparticles.The weakly adsorbed NO was reduced between 0.6 V and-0.05 V,which yielded nitrous oxide(N₂O) and ammonium(NH₄⁺) as products;while the strongly bonded NO was reduced at more negative potentials between-0.05V and-0.15V,producing only NH₄⁺ species.

Research Progress Of Synergistic Effect Of Metal Oxides On Pt-Based Catalysts, Hui-Ping Yuan, Xun Guo, Xin-Ping Qiu, Wen-Tao Zhu, Li-Quan Chen

Journal of Electrochemistry

In this paper,the work of Pt-based catalysts modified by metal oxides as the anode catalysts of direct methanol fuel cell(DMFC) is reviewed.The relationship between the structure and the composition of the catalysts and the reaction mechanism,exiting problems and developing direction are discussed.

Platinum Modified With Hydrogen Molybdenum/Tungsten Bronze As Electrocatalysts For Direct Small Organic Molecule Fuel Cell, Wei-Shan Li, Li-Peng Tian, Jun-Hua Du, Hong-Liang Huang, Wei Li, Li-Xia Zhang, Hong-Yan Yang, Pan-Pan Guo, Zhi-Hui Zhou, Xing-De Xiang, Zhao Fu

Journal of Electrochemistry

There are several problems that limit the application of direct small organic fuel cell,including the use of precious platinum and the activity loss of platinum due to the intermediates poisons from the oxidation of small organic molecules.These problems have attracted wide interest and many solutions have been proposed.We have developed a new method to reduce the platinum usage and improve its activity,based on the modification of platinum with hydrogen molybdenum/tungsten bronze(HxMo(W)O₃) was reviewed.

Preparation Of Pt Nanoflower/Zno Composites Arrays And Their Electrocatalysis For Methanol Oxidation, Li Gao, Yi-Feng E, Lou-Zhen Fan

Journal of Electrochemistry

The Pt nanoflower/ZnO(PtNF/ZnO) nanorod composites arrays were electrochemically prepared by controlling the hydrophobicity and the hydrophilicity of ZnO nanorods arrays.The Pt nanoflowers grew on the tip of ZnO nanorods,which maintain the vertical array of Zno nanorods with a high degree of size uniformity and high surface area.Compared with Pt nanoparticle covered ZnO nanorod arrays,which were prepared by controlling the hydrophilicities of ZnO nanorods and Pt nanoparticles,the PtNF/ZnO displayed highest electrocatalytic activities for the oxidation of methanol.

Enhanced Visible Light Photoelectrochemical Performances With Nitrogen Doped Tio2 Nanowire Arrays, Xiao-Jun Lv, Yue-Ming Li, Hao Zhang, Da Chen, Jennifer Hensel, Jin Z Zhang, Jing-Hong Li

Journal of Electrochemistry

Self-organized anodic anatase TiO₂ nanowire arrays doped with nitrogen have been successfully fabri-cated and their photoelectrochemical(PEC) properties have been characterized and found to be substantially im-proved compared to undoped nanowires or commercial P25 nanoparticles.Photocurrent measured with monochro-matic incident light showed that the incident photon-to-current efficiency(IPCE,%) values of nanowire arrayelectrodes with or without N-doping were obviously higher than that of commercial P25 nanoparticle electrodes,and nitrogen-doped TiO₂ nanowire arrays(NTNA) had noticeable absorption in the visible region.The NTNAelectrodes showed the highest photocurrent density and power conversion efficiency under 100 mW/cm² visiblelight illumination.A maximumolphotoconversion efficiency of 0.52% was achieved for the …

Synthesis Of α-Mno2 Microspheres For The Application In Supercapacitor, Liang Wang, Gui-Chang Liu, Zhi-Cong Shi

Journal of Electrochemistry

The MnO₂ microspheres were prepared through the oxidation of KMnO₄ and MnCO₃ microspheres precursor.The microstructure and supercapacitor properties of MnO₂ were characterized by XRD,SEM and CV.The results show that MnO₂ was in a poorly crystalline state with α-crystallographic form,the size of microspheres typically ranged from 0.5 to 2 μm.Loading 5 mg·cm^-2 MnO₂ microspheres had excellent capacitance behaviors in 2 mol·L^-1(NH₄)₂SO₄ solution.The specific capacitance was 135.6 F·g^-1 with the scan rate at 2 mV·s^-1,and 118.8 F·g^-1 with the large scan rate at 100 …

Enhanced [Ru(Bpy)3]2+-Mediated Oxidation Of Guanine Prompted By Dhp, Bao-Lian Zhang, Wei Hong, Bao-Yi Lu, Hong Li

Journal of Electrochemistry

The effects of dihexadecyl phosphate(DHP) and multi-walled carbon nanotubes(MWNTs) on the oxidation of guanine mediated by[Ru(bpy)₃]²⁺ on the ITO electrode have been investigated by cyclic voltammetry and differential pulse voltammetry.The results showed that [Ru(bpy)₃]²⁺ can mediate the oxidation.In the range from 0.01 to 0.15 mmol·L^-1,peak currents for guanine oxidation mediated by [Ru(bpy)₃]²⁺ increased with the rise of DHP concentrations.On the contrary,cationic surfactant HTAC has the ability to weaken the mediated oxidation of guanine.In addition,the oxidative mechanism of guanine mediated by [Ru(bpy)₃]²⁺ with the participation of DHP …

Electrocatalytic Activities Of Au-Mmni(3.2)Al(0.2)Mn(0.6)Co(1.00) For Borohydride Oxidation, Gui-Ling Wang, Jin-Cheng Liu, Ke-Ning Sun, Dian-Xue Cao

Journal of Electrochemistry

In this work,the electrocatalytic activities of MmNi_3.2Al_0.2Mn_0.6Co_1.0, NaOH treated MmNi_3.2Al_0.2Mn_0.6Co_1.0 and Au-MmNi_3.2Al_0.2Mn_0.6Co_1.0 obtained after NaOH treatment(Mm: misch metal) for NaBH₄ oxidation were reported. The electrodes were prepared by electrodeposition, their morphologies were analysized by SEM, their electrocatalytic properties were studied by the linear sweeping test. It was found that the oxidation current density of the Au-MmNi_3.2Al_0.2Mn_0.6Co_1.0 was 60 mA·cm^-2, it was 3.5 times higher than that at the …

Electrocatalysis Of Myoglobin-Chitosan-Au Colloid Film Modified Glass Carbon Electrode, Yu-Hua Qin, Jun Guo, Hui Xu, Li-Heng Zhou, Sheng-Tian Wang

Journal of Electrochemistry

The cyclic voltammgram of Mb/AAO/Au Colloid/GCE shows a pair of well-defined and nearly reversible peaks at about-0.20 V(vs.Ag/AgCl) in 0.1 mol/L NaAc-HAc buffer(pH = 5.4),being the characteristic peaks of the Mb heme Fe(Ⅲ) / Fe(Ⅱ)redox couples.The electron transfer between Mb and the electrode was greatly enhanced under present testing conditions.The effects of scan rate,pH and buffers concentration on the electrochemical behaviors of Mb were studied in detail.Position of the Soret absorbance band suggested that Mb in chitosan-colloidal gold hept its secondary structure similar to the native states.Oxygen was catalytically reduced by Mb in chitosan-colloidal gold films.

Index Of Recent Literatures In Electrochemical Technique And Its Applications, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

Electrochemistry Calendar, Editorial Office Of J.Electrochem.

Journal of Electrochemistry

No abstract provided.

On Being Immoderate, Stephen J. Ellmann

Other Publications

No abstract provided.

Impact Of Large Gravity Loads On Buckling Restrained Braced Frame Performance, Mark Thurgood Matthews

Theses and Dissertations

The Buckling Restrained Braced Frame (BRBF) is used in steel structures as a lateral load resisting system for seismic events. In typical design procedure the impact of gravity loads acting on BRBFs is neglected and the beams and columns of the structure are designed to resist all gravity loads. In actuality BRBFs are supporting portions of gravity loads acting on the structure which may be changing the overall performance of BRBFs. The purpose of this study is to determine the impact of large gravity loads on BRBF performance. This is done using finite element analysis to test two different structures …

Health Care And The Un Disability Rights Convention, Michael Ashley Stein, Penelope J S Stein, Dorothy Weiss, Raymond Lang

Popular Media

No abstract provided.

Mr. Eric G. Smith

African American Funeral Programs

No abstract provided.

Luther "C.W." Walden

African American Funeral Programs

No abstract provided.

Ncac Supports Censorship With Double Standards And Made Up Facts, Dan Kleinman

West Bend Community Memorial Library (Wisconsin), 2009

No abstract provided.

Obama In China: Final Thoughts

China Beat Blog: Archive 2008-2012

President Obama’s trip to China is now in the past, though there might be a postscript when the U.N. Climate Change Conference convenes in Copenhagen next month, as how China and the U.S. would cooperate (or not) in dealing with environmental issues was a major topic during Obama’s meetings with Chinese leaders. As a final look back at Obama’s first trip to China, here are several readings that put his visit in a larger context:

1. Timothy Garton Ash writes about “Two Ways for West to Meet China”, arguing that Western countries could choose between two strategies when dealing with …

11/27/2009 Obituary Records, Hawaii Obituaries

Obituaries

List of Obituaries for individuals who passed away on 11/27/2009. Scroll down to see the names and obituary description.

Eleanor Capogrosso V. Advisory Committee On Judicial

2009 Decisions

USDC for the District of New Jersey

Kenneth Taggart V. Chase Bank Usa Na

2009 Decisions

USDC for the Eastern District of Pennsylvania

Usa V. Ryan Craig

2009 Decisions

USDC for the Middle District of Pennsylvania

Donald Picano V. Emerson

2009 Decisions

USDC for the District of New Jersey