沉淀转化法制备NiO及其电化学性能研究

Research on Electrochemical Characters of NiO Prepared by Precipitation-transformation Method

采用沉淀转化法制备了Ni(OH)2前驱体,经300℃热处理后得到NiO粉末。用XRD和SEM对其结构和形貌进行表征,用循环伏安、恒流充放电和交流阻抗研究其电化学性能。结果表明,制备的NiO具有典型的赝电容特性。在沉淀转化温度为70℃,表面活性剂的浓度为20 mol/L条件下制备的NiO在3 mA/cm2的充放电电流密度下,其单电极比电容达383.8 F/g,电极电阻为0.25Ω,8 mA/cm2循环100次后,比电容为292.5 F/g,充放电效率为97.5%。

Ni（OH）2 precursors were prepared by precipitation-transformation method then NiO were obtained by calcining the prepared Ni（OH）2 under 300 ℃, The samples were characterized by XRD,SEM,cyclic voltammetry （CV）, constant current charge/discharge and electrochemical impedance spectrum（EIS）. The results indicated that NiO exhibits typical Faraday capacitance characteristics. When the concentration of surfactant was 20 mol/L and the temperature of precipitation-transformation was 70 ℃, the specific capacitance of NiO electrode could reach 383.8 F/g at 3 mA/cm^2, and the reaction resistance（RE） was 0.25 Ω, After 100 times cycles by 8 mA/cm^2 , the specific capacitance of Nio remained 292.5 F/g and the coulombic efficiency was 97.5%.