纳米非晶态Ni(OH)_2电极材料的稀土掺杂改性研究  

Study on Doping Rare Earth Modification of Nano-sized Amorphous Ni(OH)_2 Electrode Materials

作　　者：刘长久[1] 谷得龙[1] 孙丹[1] 吴华斌[1] 

机构地区：[1]桂林工学院有色金属及材料加工新技术教育部重点实验室材料与化学工程系,广西桂林541004

出　　处：《微细加工技术》2008年第2期19-22,共4页Microfabrication Technology

基　　金：广西科学研究与技术开发计划项目资助(桂科能05112001-2A1)

摘　　要：为了提高镍基二次电池正极材料的电化学性能,采用微乳液快速冷冻沉淀法制备出稀土Ce掺杂纳米级非晶态氢氧化镍粉体材料。采用Raman,XRD,SEM和TEM对其结构形态进行了表征分析,采用交流阻抗谱(EIS)和充放电性能对其电化学性能进行了测试。结果发现,掺入适量的Ce可以进一步增强纳米非晶态氢氧化镍的无序性并且使颗粒细化,进而使其电化学反应的电荷转移电阻降低,电化学活性明显增强。样品作为MH-Ni电池正极材料以0.2 C充放电,终止电压为1.0 V,当掺杂Ce的质量分数为4%时,其放电比容量达到336.7 mAh/g,这明显高于晶态β-氢氧化镍电极材料289 mAh/g的理论容量,说明纳米非晶态氢氧化镍作为高活性电极材料具有很好的应用前景。To improve the electrochemical performance of the positive material of nickel-based secondary batteries, rare earth Ce-doped amorphous nano-sized nickel hydroxide powder was prepared by rapid freezing micro-emulsion precipitation method. The structural properties of the material were characterized by Raman, XRD, SEM, TEM. The results demonstrated that the doping of Ce increases the structural disorder decreases the particle size and the electron transfer resistance, which accordingly improves the electrochemical performance dramatically. Charge-discharge test shows that when the doping content of Ce is 4%, the discharge capacity of the nano-sized amorphous nickel hydroxide at 0.2 C rate reaches 336.7 mAh/g, which is much higher the theoretical capacity of 289 mAh/g for the β-nickel hydroxide, showing its potential applications as positive material of nickel- based secondary batteries.

关 键 词：微乳液快速冷冻沉淀法 稀土Ce掺杂 纳米非晶态氢氧化镍 

分 类 号：TM911[电气工程—电力电子与电力传动]