水热对纳米氢氧化镍电化学性能的影响

本文采用微乳法制备纳米氢氧化镍，采用X射线衍射（XRD）、扫描电镜（SEM）、透射电镜（TEM）、恒流充放电、循环伏安、交流阻抗等方法研究纳米氢氧化镍的微观结构、表面形貌和电化学性能。实验结果表明：140℃水热和微乳/水热两种方式处理得到的纳米氢氧化镍具有不同形貌特征。水热和微乳/水热处理虽然不影响纳米氢氧化镍的活化性能，但对纳米氢氧化镍的放电比容量影响很大，采用140℃水热和微乳/水热处理比单纯的微乳法制备得到的纳米氢氧化镍的放电比容量分别提高了62.6 mAh/g和112.8 mAh/g。而且，处理后的纳米氢氧化镍的循环伏安峰电流增大、电荷转移电阻由2.633 Ω分别降至2.464 Ω和1.679 Ω。

Effects of Hydrothermal Modification on the Electrochemical of nano-scale Nickel Hydroxide

Nano-scale nickel hydroxide was synthesized by micro-emulsion in this paper and its structure, surface morphology and electrochemical performance were tested and analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), galvanostatic charge/discharge, cyclic voltammogram and impedance spectra. The results manifested that nano-scale nickel hydroxide turned to different morphology after hydrothermal and micro-emulsion/hydrothermal modification. Though the results of the activation performance of unsettled and treated nano-scale nickel hydroxide were uniform, the discharging specific capacity of nano-scale nickel hydroxide was changed. The discharging specific capacity of nano-scale nickel hydroxide which was under hydrothermal treatment at 140℃ and micro-emulsion/hydrothermal treatment was increased by 62.6 mAh/g and 112.8 mAh/g respectively. The peak current of cyclic voltammetry also increased and the charge-transfer resistances decreased from 2.633 Ω to 2.464 Ω and 1.679 Ω.