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 mA/g充放电电流密度下样品的首次放电比容量为1435 mAh/g,第二圈放电比容量为970 mAh/g,即使是在1000 mA/g的高电流密度下样品仍具有281.9 mAh/g的放电比容量.
Nickel hydroxide film was fabricated on nickel foam substrate in Ni (NO3)2 electrolyte by elec- trodeposition 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) 2 film with sheet-like hierarchical structure. There were many structural water mole- cules and interlayer anions in the α-Ni (OH)2 film. The electrochemical performance of the nano-sized α-Ni (OH)2 film was characterized by cyclic voltammetery (CV), electrochemical impedance spectrosco- py (EIS), and charge-discharge test. It demonstrated that the nano-sized α-Ni(OH) 2 film had very high lithium storage capacity and good rate performance. The first and second discharge capacities were up to1435 mAh/g and 970 mAh/g at a constant charge/discharge current density of 50 mA/g. This nano-sized α-Ni (OH)2 film still had a capacity of 281.9 mAh/g even at a very high charge/discharge current densi- ty of 1000 mA/g.