纳米氧化镍的低温固相合成及电容性能研究

通过低热固相反应法合成了纳米氧化镍，在不同温度热处理条件下研究氧化镍的结构、形貌及其作为超级电容器电极材料的电化学性能。采用XRD和SEM表征产物的结构特点，采用循环伏安和恒流充放电等方法表征其电化学性能。XRD测试结果表明，所制备的氧化镍为立方相，且随着热处理温度升高，晶型趋于完整。SEM和电化学测试结果表明，高温热处理（>400 ℃）使样品团聚更为严重，导致电极材料利用率降低，质子传递阻力加大，比电容急剧下降；低温处理颗粒分布均匀，粒子间存在孔道，使电极具有较大的比容量（228 F/g）和良好的化学稳定性，在20 mV/s快速扫描速率下，电极显示出良好的倍率特性。

Studies on low temperature solid-state synthesis and capacitive performance of nano-sized nickel oxide

Nano-sized nickel oxide(NiO) was synthesized by low temperature solid-state method.The structure and morphology of NiO and its electrochemical performance as electrode material for use in supercapacitor were studied under different thermal treatment conditions.The product′s structural features were investigated by XRD and SEM,and its electrochemical performance was characterized by cyclic voltammetry and galvanostastic charge-discharge method etc..Results of XRD indicated that the synthesized NiO was cubic phase and the crystal tended to be complete with the increasing temperature of heat treatment.Results of SEM and electrochemical tests showed that high temperature(>400 ℃) made a more serious conglomeration,resulting in low utilization ratio of electrode material,high resistance of proton transfer and sharply decreasing of specific capacitance;NiO particles distributed more uniformly by low temperature thermal treatment with the pore passage for the electrolyte permeation,which made electrode had high specific capacitance(228 F/g) and superior electrochemical cycling stability.Additionally it also retained a good rate performance at a scan rate of 20 mV/s.