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Full-Text Articles in Physical Chemistry
Electrochemical Performances Of Copper/Activated Carbon Composites, Lan-Ting Li, Qiang Xie, Wen Yan, Yan-Yan Wang, Wen-Wen Xing
Electrochemical Performances Of Copper/Activated Carbon Composites, Lan-Ting Li, Qiang Xie, Wen Yan, Yan-Yan Wang, Wen-Wen Xing
Journal of Electrochemistry
The development and improvement of electrode materials can result in the enhancement of the performances of electrochemical capacitor.In this paper various copper/activated carbon composites were prepared in the presence of different amounts(from 0% to 40%) of copper nitrate from bituminous coal.Then different electrodes were prepared from copper oxide,activated carbon and copper/activated carbon composites,respectively,and were characterized by cyclic voltammetry,alternative current(AC) impedance,charge-discharge at constant current and maintenance of the self-potential.The results showed that the proper amount of copper in copper/activated carbon composites positively influenced the electrochemical performances of electrodes,and the capacitance of copper/activated carbon composites was larger than that of the total …
Carbon Nanotube Array Electrodes Based Supercapacitors With 3.5v Working Voltage, Hao Zhang, Gao-Ping Cao, Yu-Sheng Yang, Zhen-Nan Gu, Bin Xu, Wen-Feng Zhang
Carbon Nanotube Array Electrodes Based Supercapacitors With 3.5v Working Voltage, Hao Zhang, Gao-Ping Cao, Yu-Sheng Yang, Zhen-Nan Gu, Bin Xu, Wen-Feng Zhang
Journal of Electrochemistry
The carbon nanotube arrays(CNTA) were grown directly on the substrates of Ta and stainless steel by chemical vapor deposition.The button-like supercapacitors were fabricated based the CNTA electrodes.The electrochemical performance of CNTA based supercapacitors presentsed high working voltage(3.5 V),long cycle life,and good rate capability.The power and energy densities are were 928 kW·kg-1 and 19 Wh·kg-1,respectively(based on the mass of CNTA).
Preparation And Electrochemical Performance Of Ordered Mesoporous Titanium Phosphate As Cathode Material For Li-Ion Battery, Qiong Wang, Attia Adel, Zhi-Cong Shi, Yong Yang
Preparation And Electrochemical Performance Of Ordered Mesoporous Titanium Phosphate As Cathode Material For Li-Ion Battery, Qiong Wang, Attia Adel, Zhi-Cong Shi, Yong Yang
Journal of Electrochemistry
Ordered porous titanium phosphate materials were prepared by using the surfactant template combined with the sol-gel method. The samples were characterized by small angle X-ray diffraction(SA-XRD) method, N2 adsorption/desorption techniques,high resolution transmission electron microscopy(HRTEM) and element analysis. It is found that the calcination temperature is a big influence on the porous structure, and electrochemical performance of the titanium phosphate materials, and the mesoporous titanium phosphate showed good performance in the electrochemical test, the first discharge capacity is 94 mAh/g at the current density of 150 mA/g. On the other hand, the no porous material with a low capacity of …
Ion-Implanting Modification Of Layered Manganese Dioxide And Its Electrochemical Performance, He-Ning Huang, Dong-Ping Lv, Xing-Kang Huang, Qi-Wei Zhang, Yong Yang
Ion-Implanting Modification Of Layered Manganese Dioxide And Its Electrochemical Performance, He-Ning Huang, Dong-Ping Lv, Xing-Kang Huang, Qi-Wei Zhang, Yong Yang
Journal of Electrochemistry
Layered MnO2(δ-MnO2) was prepared by thermal decomposition of potassium permanganate.Ti was ion-implanted into such δ-MnO2 by physical techniques,forming a composite(δ-MnO2-Ti).These materials were characterized by XRD,SEM,XPS techniques and their electrochemical proprieties were investigated.The results showed that the layered structure of δ-MnO2 did not been destroyed after Ti ion implantation,and the implanted Ti element was mainly Ti4+ as indicated by XPS.Both of the first and the highest discharge specific capacities of the ion-implanted layered MnO2(δ-MnO2-Ti),compared to those of δ-MnO2,were improved significantly.
Electrochemical Performance Of Li(1-X)MXFepo4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai
Electrochemical Performance Of Li(1-X)MXFepo4 Cathode Materials Synthesized By Polymer Pyrolysis Route, Ting Li, Jiang-Feng Qian, Yu-Liang Cao, Han-Xi Yang, Xin-Ping Ai
Journal of Electrochemistry
Olivine Li1-xMxFePO4(M=Cr3+, Mg2+, Mn2+, Ni2+) were synthesized by a polyacrylates-pyrolysis route. The structural and electrochemical properties of the as-synthesized cathode materials were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical charge/discharge cycling. The results indicate that the metallic ions doped at low concentration do not affect the crystalline structure of the material, but considerably improve the rate capability and cycle performance of LiFePO4 at high rate.
Effects On The Structure And Electrochemical Performance Of Lifepo4 By Zr4+ Doping, Yan-Li Ruan, Zhi-Yuan Tang
Effects On The Structure And Electrochemical Performance Of Lifepo4 By Zr4+ Doping, Yan-Li Ruan, Zhi-Yuan Tang
Journal of Electrochemistry
Stoichiometric Zr-doped lithium iron phosphate(LiFePO4)) cathode material was synthesized by a solid-state reaction in an inert atmosphere. The effects of doping content on the physical and electrochemical properties of as-synthesized cathode materials were investigated.The samples were characterized by powder X-ray diffraction(XRD), and their electrochemical performance was systematically measured by impedance response and constant current charge/discharge cycling tests. The results indicate that the low concentration Zr4+ doping does not affect the structure of the material but considerably improves its kinetics in terms of capacity delivery and cycle performance. At 0.1C discharging rate,the reversible specific capacities of the Li …
Effect Of Ti Doping On The Structure And Performance Of Lini0.75Co0.25O2, Hui He, Xuan Cheng, Zhang Ying, Shu-Fen Wang
Effect Of Ti Doping On The Structure And Performance Of Lini0.75Co0.25O2, Hui He, Xuan Cheng, Zhang Ying, Shu-Fen Wang
Journal of Electrochemistry
In this study,a series of Co-doped compounds with the formula of LiNi0.75-xCo0.25TixO2(x=0,(0.1),0.25)was synthesized by using sol-gel method.Their structure,particle size,electrochemical properties were studied by TG,XRD,SEM and electrochemical tests.It was shown that the structure of materials changed from a hexagonal layered structure to a cubic structure as the x value increased.In particular,a mixture of hexagonal and cubic structure was presented at x =0.25.The electrochemical performance of the materials depended strongly on the amount of Ti doping.Possible effects on the structure and performance of LiNi0.75-xCo0.25TixO2 due to Ti doping are briefly discussed …
The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou
The Influence Of Pva As Disperser On Lifepo4 Synthesized By Hydrothermal Reaction, Hui-Lin Li, Hui Zhan, Yu-Hong Zhou
Journal of Electrochemistry
LiFePO4 was synthesized by means of hydrothermal reaction,in which PVA acts as disperser and glucose as carbon source. The samples were characterized by X-ray diffraction, scanning electron microscopy and electrochemical measurement. SEM results show that the sample is homogeneously composed of grains with a particle size of ca.200nm. In the charge/discharge test, the products exhibited a 3.45V discharge voltage plateau and a maximum specific capacity of 140mAh/g. After 40 cycles, its capacity only declined by 2.1%. Besides these, the mechanism for the influence of the particle size and carbon coating on the electrochemical property of LiFePO4 material was …
Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang, Shun-Wei Zhou, Fu-Sheng Ke, Fang-Zu Yang, Xiao-Yong Fan, Shi-Gang Sun
Structure And Properties Of Electrodeposited Sn-Co Alloy Electrodes As Anode Material For Lithium-Ion Secondary Batteries, Hong-Hong Jiang, Ling Huang, Shun-Wei Zhou, Fu-Sheng Ke, Fang-Zu Yang, Xiao-Yong Fan, Shi-Gang Sun
Journal of Electrochemistry
The Sn-Co alloy deposits were prepared by electroplating.The structure and electrochemical performance of the electroplated Sn-Co alloys have been investigated in detail. Experimental results show that the porous Sn-Co alloy film exhibits hexagonal solid solution,with Sn as the solvent, Co as the solute. The texture of the Sn-Co alloy coating exhibits(110) preferred orientation. Electrochemical tests show that the porous Sn-Co alloy coating electrodes can deliver a discharge capacity of 643mAh/g in the first cycle. At the 20h cycle the charge was 461mAh/g. At initial charge curve the irreversible capacity is probably associated to a combination of processes, which may …
The Synthesis, Characteristics And Performance Of Cnt Composites As Anodic Materials In Litium-Ion Battery, Quan-Feng Dong, Ming-Sen Zheng, Zhen-Cai Huang, Ming-Gang Jin, Ya-Ding Zhan, Zu-Geng Lin
The Synthesis, Characteristics And Performance Of Cnt Composites As Anodic Materials In Litium-Ion Battery, Quan-Feng Dong, Ming-Sen Zheng, Zhen-Cai Huang, Ming-Gang Jin, Ya-Ding Zhan, Zu-Geng Lin
Journal of Electrochemistry
As an anodic material for lithium ion battery the carbon nano-tube (CNT) and some compounds based on tin have ever been investigated intensively. The fruited progress has not been made yet, however. In this paper the composites of CNT and Sn/SnO2 were synthesized employing two methods and characterized by SEM and XRD. And the electrochemical performance of the composites was investigated.
The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin
The Electrochemical Performance Of Modified Spinel At Elevated Temperature, Zhen-Ping Cai, Xiao-Hong Chen, Shi-Gang Lu, Ming-Xun Li, Wei-Hua Jin
Journal of Electrochemistry
The modified LiMn2O4 cathode materials for lithium ion batteries have been synthesized by solid-state reaction. The crystal structure and electrochemical performance of products have been investigated by SEM, XRD and electrochemical measurements. The XRD analysis indicated that all the synthesized products possess Fd3m spinel LiMn2O4 structure. Those modified LiMn2O4 materials showed improved cycling capacity over pure spinels at high temperature and room temperature.
The Electrochemical Performance Studies On Novel Lifepo4 Cathode Materials For Li-Ion Batteries, Zhi-Cong Shi, Chen Li, Yong Yang
The Electrochemical Performance Studies On Novel Lifepo4 Cathode Materials For Li-Ion Batteries, Zhi-Cong Shi, Chen Li, Yong Yang
Journal of Electrochemistry
The cathode materials of LiFePO4 and LiFePO4 coated with carbon were synthesized by means of solid state reaction and ballmilling. The samples were characterized by X-ray diffraction, scanning electron microscopy, gas-phase element analysis and titration analysis methods. Electrochemical tests of two kinds of materials showed that both of them exhibit a 3.4V discharge voltage plateau, however, the coated samples demonstrated the improved performance in terms of discharge capacity and cyclic stability.