Effect of ultrasonic on structure and electrochemical performance of α-Ni(OH)_2 electrodes  

超声波对α-Ni(OH)_2电极结构及电化学性能的影响(英文)

作　　者：张仲举[1] 朱燕娟[1] 包杰[1] 周卓均[1] 叶贤聪[1] 许庆盛[1] 

机构地区：[1]广东工业大学物理与光电工程学院,广州510006

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第12期2654-2659,共6页中国有色金属学报（英文版）

基　　金：Project (10774030) supported by the National Natural Science Foundation of China;Project (2008J1-C161) supported by the Science and Technology Program of Guangzhou City of China

摘　　要：Al/Co co-doped α-Ni（OH）2 samples were prepared by either ultrasonic co-precipitation method （Sample B） or co-precipitation method （Sample A）. The crystal structure and particle size distribution of the prepared samples were examined by X-ray diffraction （XRD） and laser particle size analyzer, respectively. The results show that Sample B has more crystalline defects and smaller average diameter than Sample A. The cyclic voltammetry and electrochemical impedance spectroscopy measurements indicate that Sample B has better electrochemical performance than Sample A, such as better reaction reversibility, lower charge-transfer resistance and better cyclic stability. Proton diffusion coefficient of Sample B is 1.96×10-10cm2/s, which is two times as large as that （9.78×10-11cm2/s） of Sample A. The charge-discharge tests show that the discharge capacity （308 mA·h/g） of Sample B is 25 mA·h/g higher than that of Sample A （283 mA·h/g）.分别采用共沉淀法和超声波共沉淀法制备Al/Co复合掺杂α-Ni(OH)2样品A和B,用XRD和激光粒度仪表征样品的晶相结构和粒度分布。结果表明,样品B比样品A具有较多的晶格缺陷和较小的平均粒径。循环伏安特性及电化学阻抗谱测试显示,样品B比样品A具有更好的电化学性能:较好的反应可逆性、较低的电荷转移电阻和较高的循环寿命等。样品B的质子扩散系数为1.96×10-10cm2/s,约为样品A(9.78×10-11cm2/s)的2倍。充放电测试显示,样品B的放电比容量达到308mA·h/g,比样品A的放电比容量高25mA·h/g。

关 键 词：Al/Co co-doped α-Ni（OH）2 ultrasonic co-precipitation method proton diffusion coefficient charge-transfer resistance electrochemical performance 

分 类 号：O646[理学—物理化学] TM912.2[理学—化学]