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Articles 541 - 570 of 1920

Full-Text Articles in Materials Science and Engineering

Thermo-Stability And Active Site Structure Of Fe/N/C Electrocatalyst For Oxygen Reduction Reaction, Chi Chen, Yu-Jiao Lai, Zhi-You Zhou, Xin-Sheng Zhang, Shi-Gang Sun Aug 2017

Thermo-Stability And Active Site Structure Of Fe/N/C Electrocatalyst For Oxygen Reduction Reaction, Chi Chen, Yu-Jiao Lai, Zhi-You Zhou, Xin-Sheng Zhang, Shi-Gang Sun

Journal of Electrochemistry

The development of Fe/N/C electrocatalyst for oxygen reduction reaction (ORR) is vital for the large-scale applications of proton exchange membrane fuel cells. Understanding the active site structure will contribute to the rational design of highly active catalysts. In this study, the as-prepared Fe/N/C catalyst based on poly-m-phenylenediamine (PmPDA-FeNx/C) catalyst with the high ORR activity was subjected to the high-temperature heat treatment again at 1000 ~1500 oC. The degradation of in the ORR activity of PmPDA-FeNx/C by with various heat treatments was correlated to the change of elemental compositions, chemical states and textural properties. As the …

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Electric Current Induced Flow And Electrocapillary Deformation Of Liquid Wood Alloy In Naoh Aqueous Solution, Guo-Di Zhang, Qiao-Li Lin, Jian-Hong Cheng, Rui Cao Aug 2017

Electric Current Induced Flow And Electrocapillary Deformation Of Liquid Wood Alloy In Naoh Aqueous Solution, Guo-Di Zhang, Qiao-Li Lin, Jian-Hong Cheng, Rui Cao

Journal of Electrochemistry

The phenomena of the electric current induced flow and electrocapillary deformation for a liquid Wood alloy in a NaOH electrolyte were studied. Electrocapillary behaviors for the liquid Wood alloy in NaOH electrolytes by applying external low voltages were investigated. The electrode reaction (redox reaction) induced the formation or removing removal of an oxide film, and further caused the drop deformation by decreasing or increasing an interfacial tension. The same polar charge in the electric double layer would also decrease the interfacial tension. In order to maintain the stability of system, the contact area of the interface would be expanded, and …

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Influence Of Typical Anions In Seawater Environments On Corrosion Behaviors Of 5083 Aluminum Alloy, Yang-Fan Tu, Li-Ming Feng, Zhi-Gang Fang, Hai-Tao Liu, Ming-Hua Jing, Yong Guan Aug 2017

Influence Of Typical Anions In Seawater Environments On Corrosion Behaviors Of 5083 Aluminum Alloy, Yang-Fan Tu, Li-Ming Feng, Zhi-Gang Fang, Hai-Tao Liu, Ming-Hua Jing, Yong Guan

Journal of Electrochemistry

The interaction effects of typical anions, namely, Cl-, HCO3- and SO42-, presented in seawater environments on corrosion resistance behaviors of AA5083 aluminum alloy have been studied. The corrosion resistances of the 5083 aluminum alloy in different simulated seawater environments were tested by factorial analysis method. The polarization curves, the corrosion potentials, corrosion current densities and the breakdown potentials were examined in different concentrations of Cl-, HCO3- and SO42-.The corrosion behavior was analyzed by electrochemical impedance spectroscopy (EIS). The results showed that both Cl-,  and …

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Tetrabutylammonium Hexafluorophosphate As Flame Retardant Additive For Lithium Ion Batteries, Qing Zhao, Qian Zhang, Jing-Min Fan, Ming-Sen Zheng, Quan-Feng Dong Aug 2017

Tetrabutylammonium Hexafluorophosphate As Flame Retardant Additive For Lithium Ion Batteries, Qing Zhao, Qian Zhang, Jing-Min Fan, Ming-Sen Zheng, Quan-Feng Dong

Journal of Electrochemistry

Safety issues have been attracted more and more attentions due to the wide applications of lithium ion batteries. Introducing flame retardant additives are one of the effective strategies to improve the safety of lithium-ion batteries. In this paper, the tetrabutylammonium hexafluorophosphate (TBAPF6) as a flame retardant additive was added to the electrolyte as a flame retardant additive to enhance the safety of lithium ion batteries. The self-extinguishing time (SET) and ionic conductivities of the electrolytes with different TBAPF6 contents were investigated. It is found that TBAPF6 dramatically reduced the flammability of the electrolyte while slightly decreasing ionic …

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Electrochemical Performance Of Sodium Difluoro(Oxalato)Borate As The Additive Of Non-Aqueous Electrolytes For Sodium-Ion Batteries, Ding Zhang, Qin Zhu, Ying Wang, Cheng-Long Zhao, Shi-Bin Liu, Shou-Dong Xu Aug 2017

Electrochemical Performance Of Sodium Difluoro(Oxalato)Borate As The Additive Of Non-Aqueous Electrolytes For Sodium-Ion Batteries, Ding Zhang, Qin Zhu, Ying Wang, Cheng-Long Zhao, Shi-Bin Liu, Shou-Dong Xu

Journal of Electrochemistry

Sodium ion battery has attracted worldwide and intensive attention recently, while the adoption of electrolyte additives has been considered as one effective strategy to promote the cell performance. Within this work sodium difluoro(oxalato)borate (NaDFOB) was prepared and adopted as an additive for the general non-aqueous electrolyte formula of 1 mol·L-1 NaClO4/EC/PC (Vol: Vol=1:1), and the effects of the additive concentration on ionic conductivity and oxidization decomposition voltage were investigated in detail. In addition, the cell performance evaluated by NaNi0.5Mn0.5O2 as the cathode was also studied. It reveals that the addition of NaDFOB into the NaClO4/EC/PC electrolyte resulted in the significantly …

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An Investigation Of The Synergistic Effect Between (1,3-Dioxolan-2-Ylmethyl)Triphenylphosphonium Bromide And Iodide Ion For The Corrosion Inhibition Of Zinc In Citric Acid, Saadawy M. Aug 2017

An Investigation Of The Synergistic Effect Between (1,3-Dioxolan-2-Ylmethyl)Triphenylphosphonium Bromide And Iodide Ion For The Corrosion Inhibition Of Zinc In Citric Acid, Saadawy M.

Journal of Electrochemistry

The effect of (1,3-Dioxolan-2-ylmethyl)-triphenylphosphonium bromide (DTPB) on the zinc corrosion in 0.5 mol·L-1 citric acid solution was investigated at 30 oC using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. An ecofriendly bath was used for acid cleaning of zinc, which has not been widely used in literatures. The results showed that DTPB could serve as an effective inhibitor for the zinc corrosion in a citric acid solution with the inhibition efficiency of 98.9% at the DTPB concentration of 3×10-3 mol·L-1. A synergistic effect between DTPB and potassium iodide (KI) enhanced the inhibition …

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Density Functional Investigation On Cathode/Electrolyte Interface In Solid-State Lithium Batteries, Xuelong Wang, Ruijuan Xiao, Yong Xiang, Hong Li, Liquan Chen Aug 2017

Density Functional Investigation On Cathode/Electrolyte Interface In Solid-State Lithium Batteries, Xuelong Wang, Ruijuan Xiao, Yong Xiang, Hong Li, Liquan Chen

Journal of Electrochemistry

The rapidly expanding application of lithium ion batteries stimulates research interest on energy storage devices with higher energy density, better safety and faster charge/discharge speed. All-solid-state lithium batteries have been considered as promising candidates because of their fewer side reactions and better safety compared with conventional lithium-ion batteries with organic liquid electrolytes. Looking for well-matched electrode/electrolyte interfaces is one of the keys to ensuring good comprehensive performance of solid-state lithium batteries. In this report, with the aid of first-principles simulations, the local structure and lithium ions transportation properties of electrolyte surfaces and cathode/electrolyte interfaces are investigated. The β-Li3PS …

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A New Type Carbon Composited Molybdenum Doped Vanadium Oxide Nanowires As A Cathode Material For Sodium Ion Batteries, Guang-Rui Zhang, Li-Qiang Hu, Bao-Zhu Zhang Aug 2017

A New Type Carbon Composited Molybdenum Doped Vanadium Oxide Nanowires As A Cathode Material For Sodium Ion Batteries, Guang-Rui Zhang, Li-Qiang Hu, Bao-Zhu Zhang

Journal of Electrochemistry

In recent years, the development of lithium ion batteries (LIBs) has been limited due to the insufficient lithium resource and increasing cost. As a promising candidate, sodium ion batteries (SIBs) with the similar electrochemical mechanism and lower cost than LIBs are developing rapidly. However, as a result of the larger radius of Na+ compared with Li+, the crystalline structures of the most electrode materials are damaged severely during the intercalation of Na+, which limits the electrochemical properties of SIBs. Thus, developing new types of electrode materials for SIBs is particularly important. Among the cathode materials, …

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Effects Of Temperature On The Nucleation And Growth Mechanism Of Pbo2 Electrodeposition, Lei Wang, Juan-Qin Xue, Li-Hua Yu, Chang-Bin Tang, Qiang Bi Aug 2017

Effects Of Temperature On The Nucleation And Growth Mechanism Of Pbo2 Electrodeposition, Lei Wang, Juan-Qin Xue, Li-Hua Yu, Chang-Bin Tang, Qiang Bi

Journal of Electrochemistry

In order to investigate the effects of temperature on the nucleation and growth of lead dioxide (PbO2), the in situ electrochemical depositions of PbO2 were carried out on the glassy carbon electrode at different temperatures, namely, 25℃,35℃, 45℃, 55℃, and 65℃.The cyclic voltammetric curves, the time-current and the time-potential curves,SEM images and XRD patterns of the PbO2 coatings deposited at different temperatures were obtained. The results showed that the PbO2 underwent nucleation and grew at different temperatures. The 3D continuous nucleation mode of PbO2 electrodeposition remained unchanged with the increase of temperature. However, the …

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Effects Of Surface Modification Modes On Proton-Over-Vanadium Ion Selectivity Of Nafion®Membrane For Application In Vanadium Redox Flow Battery, Qing-Long Tan, Hai-Ning Wang, Shan-Fu Lu, Da-Wei Liang, Chun-Xiao Wu, Yan Xiang Aug 2017

Effects Of Surface Modification Modes On Proton-Over-Vanadium Ion Selectivity Of Nafion®Membrane For Application In Vanadium Redox Flow Battery, Qing-Long Tan, Hai-Ning Wang, Shan-Fu Lu, Da-Wei Liang, Chun-Xiao Wu, Yan Xiang

Journal of Electrochemistry

The effect of surface modification modes on proton-over-vanadium ion selectivity was studied by spin-coating chitosan-Phosphotungstic Acid (PWA) as a single or double layer on Nafion membrane surface. To suppress the vanadium ions permeation through the Nafion? membrane in a vanadium redox flow battery (VRFB), the single surface-modified Nafion membrane (Nafion/chitosan-PWA)S and double surface-modified Nafion membrane (Nafion/chitosan-PWA)D demonstrated a 89.9% and 92.7% reduction of vanadium ion permeability in comparison with pristine Nafion, respectively. The (Nafion/chitosan-PWA)D exhibited betterhigher selectivity between proton and vanadium ions than the (Nafion/chitosan-PWA)S at the same layer thickness. Furthermore, the columbic efficiency for the VRFB single cell based …

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Wastewater Treatment Process Based On Microbial Electrochemistry: Opportunities And Challenges, Wei-Hua He, Jia Liu, Hai-Man Wang, Yu-Jie Feng Jun 2017

Wastewater Treatment Process Based On Microbial Electrochemistry: Opportunities And Challenges, Wei-Hua He, Jia Liu, Hai-Man Wang, Yu-Jie Feng

Journal of Electrochemistry

Microbial electrochemical technology (MET) has drawn great attention for its characteristics of synergetic pollution removal and energy recovery of wastewater. In the last decade, significant developments in microbial electrochemical system (MES) have been made in the aspects of electron transfer mechanism, microbial community analysis, function expansion, low-cost electrode materials and scaled-up constructions. However, the feasibility of MET as a wastewater treatment process has been controversial so far. In this paper, the characteristics of MET were systematically compared with anaerobic and aerobic processes from the application point of view in the aspects of pollution degradation and energy recovery processes. The MET-based …

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Ionic Liquid-Supported Tempo/Polymeric Ionic-Liquid/Carbon Black Ternary Composites: Preparations And Applications In Electrochemical Oxidation Of Alcohols, Xin Lin, Cao-Cao Sun, Zhi-Rong Liu, Cheng-Chu Zeng Jun 2017

Ionic Liquid-Supported Tempo/Polymeric Ionic-Liquid/Carbon Black Ternary Composites: Preparations And Applications In Electrochemical Oxidation Of Alcohols, Xin Lin, Cao-Cao Sun, Zhi-Rong Liu, Cheng-Chu Zeng

Journal of Electrochemistry

To effectively recover redox catalyst and supporting electrolyte, a novel ternary composite consisting of ionic liquid-supported TEMPO, polymeric ionic-liquid and carbon black was prepared. The ionic-liquid supported redox catalyst TEMPO-IL-BF4 was firstly synthesized from 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, and followed by the reaction of polydimethyldiallylammonium chloride (PDDA) and bis(trifluoromethane)sulfonimide lithium salt (LiTFSI) to form poly[diallyldimethylammonium bis(trifluoromethanesulfonyl)imide] (PDDA(Tf2N)). A combination of the above mentioned two synthesized materials and carbon black afforded to obtain the ternary composite, which was used as the recoverable supporting electrolyte and mediator for the electrochemical oxidation of alcohol. The results indicate that various alcohols could be oxidized …

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Electrochemical Synthesis Of Homoallylic Alcohols And Homoallylic Amines, Wei-Qiang Zhong, Xiang-Hui Liang, Jing-Mei Huang Jun 2017

Electrochemical Synthesis Of Homoallylic Alcohols And Homoallylic Amines, Wei-Qiang Zhong, Xiang-Hui Liang, Jing-Mei Huang

Journal of Electrochemistry

Electrochemical technique has been widely applied in the organic synthesis. This review focuses on the electrochemical synthesis of homoallylic alcohols and homoallylic amines from the allylation of carbonyl compounds and imines. This method has been developed impressively, especially in the field of electrochemical allylation in a green solvent of aqueous media. Improvement of the efficiency of the electricity, regio-selectivity and chiral synthesis are expected.

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Preparations And Applications Of Irsnox Electrode In Electrochemical Synthesis Of 2,5-Dichlorophenol, Xiang-Yu Ma, Xu-Guo Tu, Rui-Nan He, Ya Chen, Gui-Sheng Zhu, Shou-Yan Shao, Song Chen Jun 2017

Preparations And Applications Of Irsnox Electrode In Electrochemical Synthesis Of 2,5-Dichlorophenol, Xiang-Yu Ma, Xu-Guo Tu, Rui-Nan He, Ya Chen, Gui-Sheng Zhu, Shou-Yan Shao, Song Chen

Journal of Electrochemistry

The electrodes of titanium based iridium tin oxides (IrSnOx) have been prepared by traditional thermal decomposition method and further applied to the electrosynthsis of 2,5-dichlorophenol in order to explore a green and high efficient synthesis route. The results showed that the electrode surface existed apparent cracks, while the intermediate layer prepared with Sn:Sb=94:6 existed less cracks and longer life time. The main products of the electrolytic reaction were 2,5-dichlorophenol, p-chlorophenol, and 1,2,4-trichlorobenzene. The electrosynthsis yield of 2,5-dichlorophenol reached 57% and the selectivity of 2,5-dichlorophenol was as high as 93% by using the IrSnOx as an anode, which is obviously better …

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Electrochemical Deposition Of Cr From Cr3+ In The Mixed Electrolyte Of [Bmim]Oac/H2O, Wei Luo, Dong-Fang Niu, Rong-Bin Du, Jun-Wei Wang, Zhu-Qing Wang, Heng Xu, Xin-Sheng Zhang Jun 2017

Electrochemical Deposition Of Cr From Cr3+ In The Mixed Electrolyte Of [Bmim]Oac/H2O, Wei Luo, Dong-Fang Niu, Rong-Bin Du, Jun-Wei Wang, Zhu-Qing Wang, Heng Xu, Xin-Sheng Zhang

Journal of Electrochemistry

The electrochemical reduction of trivalent chromium ion (Cr3+) to Cr in 1-butyl-3-methylimidazolium acetate ([BMIM]OAc)-H2O mixed electrolyte was investigated. The cyclic voltammograms showed that the electroreduction of Cr3+ in the mixed electrolyte occurred in a two-step process, namely, Cr3+ + e → Cr2+ and Cr2+ + 2e→ Cr0, controlled by the diffusion of Cr3+ to the electrode. The diffusion coefficient of Cr3+ was 1.2×10-8 cm2/s at 40 ℃ obtained by Rendle-Sevcik equation. The chronoamperomograms of the Cr3+ electrodeposition confirmed the three-dimensional instantaneous nucleation mechanism of …

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Preparations And Characterizations Of Ti/Pbo2 Electrodes Modified With Rare Earth Of Praseodymium And Pvp In Electrochemical Degradation Of Organics, Mai Xu, Feng-Wu Wang, Xian Liang, Yi-Jun Wei, Wen-Yan Fang, Chuan-Gao Zhu, Yun-Hu Hun Jun 2017

Preparations And Characterizations Of Ti/Pbo2 Electrodes Modified With Rare Earth Of Praseodymium And Pvp In Electrochemical Degradation Of Organics, Mai Xu, Feng-Wu Wang, Xian Liang, Yi-Jun Wei, Wen-Yan Fang, Chuan-Gao Zhu, Yun-Hu Hun

Journal of Electrochemistry

The titanium (Ti) based lead oxide (PbO2) electrodes doped with praseodymium oxide (Pr2O3) and polyvinylpyrrolidone (PVP) were prepared by electrodeposition. The surface morphologies and structures of the as-prepared thin films were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) technique, respectively. The results showed that the denser and more uniform coatings with smaller particles and larger surfaces were obtained by doping, which modified the micro-structure of the Ti/SnO2-Sb2O3/Pr2O3-PVP-PbO2 electrode. Cyclic voltammetry (CV) was also used to study the electrocatalytic activity of …

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Electrocatalysis Of Nanotin Dioxide In The Battery Reaction Of Zinc-Nitrobenzene, Xu-Guo Tu, Xiang-Yu Ma, Rui-Nan He, Xiao-Juan Wang, Chen Ling, Yun-Xia Sun, Song Chen Jun 2017

Electrocatalysis Of Nanotin Dioxide In The Battery Reaction Of Zinc-Nitrobenzene, Xu-Guo Tu, Xiang-Yu Ma, Rui-Nan He, Xiao-Juan Wang, Chen Ling, Yun-Xia Sun, Song Chen

Journal of Electrochemistry

The tin dioxide (SnO2) nanoparticles were synthesized by using a simple hydrothermal route in the presence of tetrapropyl ammonium bromide (TPAB) as a surfactant. Accordingly, the titanium mesh based SnO2 catalyst electrode was prepared. The morphologies and structures of SnO2 nanostructures were characterized by scanning electron microscopy and X-ray diffraction spectrometry. The influences of reactant concentration, reaction temperature and time on the morphology of the products were investigated in detail. The electrocatalytic performance of SnO2 for the reduction of nitrobenzene with zinc was studied. Possible formation process and growth mechanism for such hierarchical SnO2 …

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Selective Direct Electro-Oxidation Of C-H Bond, Yan-Mei Liao, Qian-Qian Wu, An-Lun Zhang, Ying-Hong Zhu, Chun-An Ma Jun 2017

Selective Direct Electro-Oxidation Of C-H Bond, Yan-Mei Liao, Qian-Qian Wu, An-Lun Zhang, Ying-Hong Zhu, Chun-An Ma

Journal of Electrochemistry

Carbon-hydrogen (C-H) bond is the most basic chemical bond in organic compounds. The activation and direct conversion of C-H bond are the effective methodology for synthesis of different kinds of organic compounds from alkane compounds. The oxidative activation and functionalization of C-H bonds constitute an important and challenging area of investigation. The electro-oxidative activation of C-H bonds to form new C-O, C-C and C-N bonds has proven to be interesting and important in organic chemistry using the clean electron as the oxidant. The target C-O, C-C and C-N compounds could be selectively achieved by choosing the appropriate electrode, supporting electrolyte …

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Electrocarboxylation: An Effective Process For Fixation Of Co2 Into Organic Carboxylic Acids, Huan Wang, Jia-Xing Lu Jun 2017

Electrocarboxylation: An Effective Process For Fixation Of Co2 Into Organic Carboxylic Acids, Huan Wang, Jia-Xing Lu

Journal of Electrochemistry

Conversion and utilization of greenhouse gas carbon dioxide (CO2) have become more and more significant to the sustainable development of the global economy. Among them, electrocarboxylation of organic substrates is an effective process. Under mild conditions such as ambient temperature and pressure, carbocations generated by electroreduction of organic substrates can react with CO2 into corresponding carboxylic acids. This paper introduces the recent progress of our group in electrochemical carboxylation, including electrocarboxylation of varies active organic substrates and asymmetric electrocarboxylation.

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Recent Progress In Template-Assisted Synthesis Of Nitrogen-Doped Porous Carbons For Oxygen Electroreduction, Wenhan Niu, Ligui Li, Shaowei Chen Apr 2017

Recent Progress In Template-Assisted Synthesis Of Nitrogen-Doped Porous Carbons For Oxygen Electroreduction, Wenhan Niu, Ligui Li, Shaowei Chen

Journal of Electrochemistry

Nitrogen (N)-doped porous carbons are potential alternatives to precious metal catalysts for oxygen reduction reaction (ORR) at the cathodes of proton exchange membrane fuel cells and metal-air batteries. Template-assisted synthesis has been used extensively as a robust and versatile method in the preparation of such carbon catalysts, where the ORR activity has been found to be dependent on various structural parameters, such as the concentrations and molecular configurations of the dopants, and the porosity, surface accessibility and electrical conductivity of the carbon materials. In this review, we summarize recent progress in this area of research focusing on the design, preparation …

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Comparison Of Oxygen Reduction Reaction Activity Of Pt-Alloy Nanocubes, Yongan Tang, Lin Dai, Shouzhong Zou Apr 2017

Comparison Of Oxygen Reduction Reaction Activity Of Pt-Alloy Nanocubes, Yongan Tang, Lin Dai, Shouzhong Zou

Journal of Electrochemistry

Alloying Pt with the first row non-noble transition metals has been demonstrated to increase the catalytic activity toward oxygen reduction reaction (ORR), which is the cathode reaction of the proton exchange membrane fuel cells (PEMFCs) and metal-air batteries. However, how much the ORR activity improvement comes from the alloying elements remains controversial. In this paper, the nanocubes of PtMn, PtFe, PtCo, and PtNi with the similar size and composition were prepared and their ORR activities were explored, in order to investigate the effects of alloying elements on the catalytic activity. The use of cubic shape particles minimizes the contribution to …

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Designing Pt-Skin Of Pt-Based Bimetallic Electrocatalysts For Oxygen Reduction Reaction, Binwei Zhang, Yunxiao Wang, Yanfei Xu, Huakun Liu, Shixue Dou Apr 2017

Designing Pt-Skin Of Pt-Based Bimetallic Electrocatalysts For Oxygen Reduction Reaction, Binwei Zhang, Yunxiao Wang, Yanfei Xu, Huakun Liu, Shixue Dou

Journal of Electrochemistry

In the past decade, great advancement has been made in the development of nanocatalysts for energy conversion and storage. Pt-skin of Pt-based bimetallic has shown a great potential in the tuning the electronic structures of electrocatalytically active materials toward oxygen reduction reaction. Here, we offer a brief overview of the recent research on the design and preparation of catalysts. Our focus is paid on the systematic studies of preparation and performance of Pt-skin catalysts towards oxygen reduction reaction.

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Comparative Studies Of Fe, Ni, Co And Their Bimetallic Nanoparticles For Electrochemical Water Oxidation, Maduraiveeran Govindhan, Brennan Mao, Aicheng Chen Apr 2017

Comparative Studies Of Fe, Ni, Co And Their Bimetallic Nanoparticles For Electrochemical Water Oxidation, Maduraiveeran Govindhan, Brennan Mao, Aicheng Chen

Journal of Electrochemistry

The design of efficient, durable, and earth-abundant electrocatalysts via environmentally compatible strategies for the oxygen evolution reaction (OER) is a vital for energy conversion processes. Herein we report a facile approach for the fabrication of low-cost and earth abundant metal catalysts, including iron (Fe), nickel (Ni), cobalt (Co), CoNi, and CoFe nanoparticles (NPs) on titanium (Ti) substrates through a one-step electrochemical deposition. Field-emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) spectrocopy, X-ray photoelectron spectroscopy (XPS), and electrochemical techniques were employed to characterize these nanoparticles. Our electrochemical results revealed that among the five synthesized nanomaterials, the …

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Impact Of Nafion Loading And Anion Adsorption On The Synthesis Of Pt Monolayer Core-Shell Catalysts, Lijun Yang, Dustin Banham, Elod Gyenge, Siyu Ye Apr 2017

Impact Of Nafion Loading And Anion Adsorption On The Synthesis Of Pt Monolayer Core-Shell Catalysts, Lijun Yang, Dustin Banham, Elod Gyenge, Siyu Ye

Journal of Electrochemistry

Carbon supported palladium (Pd) nanoparticles were used as a model core material for the synthesis of platinum (Pt) monolayer core-shell catalysts using rotating disk electrode method and a copper (Cu) under potential deposition technique. The impact of Nafion on the synthesis process was revealed by electrochemical testing with various Nafion contents. The existence of Nafion influenced the Cu under potential deposition, galvanic replacement and eventually the oxygen reduction reaction activity of the core-shell catalyst. However, as long as the Nafion content was less than 5 wt% in the test film, adding Nafion could help to bind catalyst onto the surface …

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Novel Composites Between Nano-Structured Nickel Sulfides And Three-Dimensional Graphene For High Performance Supercapacitors, Xiaomin Wang, Huanglin Dou, Zhen Tian, Jiujun Zhang Apr 2017

Novel Composites Between Nano-Structured Nickel Sulfides And Three-Dimensional Graphene For High Performance Supercapacitors, Xiaomin Wang, Huanglin Dou, Zhen Tian, Jiujun Zhang

Journal of Electrochemistry

In this paper, a three-dimensional graphene (3DG) network grown on nickel foam was employed as a template for synthesizing graphene-based composite materials of supercapacitor electrode. The composites (crystal Ni3S2 nanorods on the surface of 3DG (abbreviated as Ni3S2/3DG)) were obtained through a one-step hydrothermal reaction. The morphological and structural evolution of the Ni3S2/3DG composites were investigated by SEM, TEM, XRD and Raman spectroscopy. Detailed electrochemical characterization showed that the Ni3S2/3DG-coated electrodes exhibited both a specific capacitance as high as 1825 F·g-1 at 5 mV·s …

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Electrodeposition Of Ruo2 Layers On Tio2 Nanotube Array Toward Co2 Electroreduction, Bei Jiang, Lina Zhang, Xianxian Qin, Wenbin Cai Apr 2017

Electrodeposition Of Ruo2 Layers On Tio2 Nanotube Array Toward Co2 Electroreduction, Bei Jiang, Lina Zhang, Xianxian Qin, Wenbin Cai

Journal of Electrochemistry

RuO2/TiO2 composite materials have multitude of electrocatalytic applications including but not limited to CO2 reduction reaction (CO2RR). RuO2/TiO2 electrodes were previously prepared by repetitive coating and thermal decomposition (TD) of a Ru(III) precursor solution on Ti substrate. In this work, electrochemical potential cycling is applied to deposit amorphous RuO2 (α-RuO2) layers onto TiO2 nanotube array (TNA) (RuO2CV/TNA) preformed on Ti foil. SEM, GIXRD, and voltammetry are applied to characterize the structures of the resulting RuO2CV/TNA. Ru loading on the RuO2 …

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Performance Of Piperidine Ionic Liquid Based Mixed Electrolyte In Li/Licoo2 Cell, Hu Cheng, Xiao-Yan Nie, Ye-Dan Shen Feb 2017

Performance Of Piperidine Ionic Liquid Based Mixed Electrolyte In Li/Licoo2 Cell, Hu Cheng, Xiao-Yan Nie, Ye-Dan Shen

Journal of Electrochemistry

The N-methyl-N-ethyl (propyl, butyl) piperidinium bis (trifluo romethanesulfonyl) imide (PP12(3,4)TFSI) ionic liquids were prepared, and their influences on the performances of Li/LiCoO2 cells were investigated. The electrochemical performance and thermostability of ionic liquids based mixed electrolytes were characterized by electrochemical methods and thermogravimetric analysis. The results showed that the piperidine ionic liquids could improve the thermostability of organic electrolyte, and the size of their side chain had played an important role on the electrochemical performance of Li/LiCoO2 cell. The Li/LiCoO2 cell used the electrolyte mixed with PP13TFSI exhibited the best electrochemical performance among the three ionic liquids. …

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The Problem Of The Anode Electrolyte In H-Type Electrolytic Cell For Electrochemical Reduction Of Carbon Dioxide, Rui Zhang, Wei-Xin Lv, Li-Xu Lei Feb 2017

The Problem Of The Anode Electrolyte In H-Type Electrolytic Cell For Electrochemical Reduction Of Carbon Dioxide, Rui Zhang, Wei-Xin Lv, Li-Xu Lei

Journal of Electrochemistry

Electrochemical reduction of carbon dioxide (CO2) was studied in the H-type electrolytic cell. It was found that the voltage between the cathode and the anode would increase during the long time electrolysis process, for this reason the electrolytic process would be unsustainable. After the experimental investigations carried out by constant potential electrolysis, constant current electrolysis, pH test and KHCO3 concentration analysis of anode electrolyte before and after the electrolysis, the increase in cell voltage might be caused by the following process: H+, that was generated from the anodic oxygen evolution reaction, reacted with HCO3 …

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Effects Of Flame Retardant On The Rate Capability And Safety Performances Of The Soft-Package 5ah Lithium Ion Battery, Yan-Zhuo Lv, Xiao-He Wang, Yi-Ming Qin, Zhen-Bo Wang, Ke Ke Feb 2017

Effects Of Flame Retardant On The Rate Capability And Safety Performances Of The Soft-Package 5ah Lithium Ion Battery, Yan-Zhuo Lv, Xiao-He Wang, Yi-Ming Qin, Zhen-Bo Wang, Ke Ke

Journal of Electrochemistry

The 5 Ah soft packed lithium ion batteries with LiNi 0.4Co0.2Mn0.4 O2 as the positive electrode material and the organic electrolytes with different amounts of fire retardants as the electrolyte solution were prepared. The effects of the fire retardant amount (5 %,10 %,20 %) of the fire retardants on the rate performances, short-circuit characteristics and overcharged behaviors of the 5 Ah soft packed lithium ion battery were investigated by electrochemical methods. The results indicated that the best rate performances were obtained by adding 5 vol.% of the fire retardants in the electrolyte solution when the …

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Application Of Composite Ionic Liquid In Electro-Oxidation Activation Of A C-H Bond, Zi-Ying Chen, Qian-Qian Wu, Jian-Qing Zhang, Ying-Hong Zhu, Chun-An Ma Feb 2017

Application Of Composite Ionic Liquid In Electro-Oxidation Activation Of A C-H Bond, Zi-Ying Chen, Qian-Qian Wu, Jian-Qing Zhang, Ying-Hong Zhu, Chun-An Ma

Journal of Electrochemistry

In this paper, the ionic liquid/carbon nanotube composite material was prepared through modifying the ionic liquid 1-ethyl-3-methylimidazolium acetate to multi-walled carbon nanotubes. The electro-oxidation properties of p-methoxy toluene (p-MT) were studied using the composite as an electrolyte. The effects of scanning speed, temperature and substrate concentration were studied by cyclic voltammetry and chronoamperometry. The electrochemical kinetics of p-MT in this system was also studied. The results showed that the electrochemical oxidation of p-MT in the composite electrolyte solution was irreversible. The process was mainly controlled by diffusion, and the diffusion coefficient (D) was 7.69×10-10 cm2·s-1. Increasing …

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