纳米α-Ni(OH)_2的电沉积制备及其嵌锂性能研究-《电镀与精饰》

文章信息/Info

Title:: Preparation of Nano-sized α-Ni(OH)_2 by Electrodeposition Method and Its Lithium Storage Performance

作者:: 潘观林; 姚金环; 朱文凤; 李延伟; 张灵志; 广西矿冶与环境科学实验中心；桂林理工大学化学与生物工程学院;桂林理工大学有色金属及材料加工新技术教育部重点实验室

摘要:: 以Ni(NO3)2水溶液为电解液,通过电沉积法在泡沫镍基体上原位生长了Ni(OH)2薄膜。采用X-射线衍射、傅里叶变换红外光谱、热重分析和场发射扫描电子显微镜对样品的微观结构进行了分析,发现该样品是具有片状纳米次级结构的α-Ni(OH)2,其内部含有一定量的结晶水和层间阴离子;采用循环伏安、交流阻抗和充放电测试研究了样品的嵌锂性能,结果表明该样品具有很高的嵌锂活性和良好的倍率性能,在50 m A/g充放电电流密度下样品的首次放电比容量为1 435 m Ah/g,第二圈放电比容量为970 m Ah/g,即使是在1 000 m A/g的高电流密度下样品仍具有281.9 m Ah/g的放电比容量。

Abstract:: Nickel hydroxide film was fabricated on nickel foam substrate in Ni( NO3)2electrolyte by electrodeposition method. The microstructure of the prepared sample was analyzed by X-ray diffraction( XRD),Fourier transform infrared spectroscopy( FT-IR),thermo-gravimetric analysis( TGA),and field emission scanning electron microscopy( FESEM). It revealed that the prepared nickel hydroxide was nano-sized α-Ni( OH)2film with sheet-like hierarchical structure. There were many structural water molecules and interlayer anions in the α-Ni( OH)2film. The electrochemical performance of the nano-sizedα-Ni( OH)2film was characterized by cyclic voltammetery( CV),electrochemical impedance spectroscopy( EIS),and charge-discharge test. It demonstrated that the nano-sized α-Ni( OH)2film had very high lithium storage capacity and good rate performance. The first and second discharge capacities were up to1435 m Ah / g and 970 m Ah / g at a constant charge / discharge current density of 50 m A / g. This nano-sizedα-Ni( OH)2film still had a capacity of 281. 9 m Ah / g even at a very high charge / discharge current density of 1 000 m A / g.