α-MnO_2微球的制备及其电化学电容性质

Preparation and Electrochemical Capacitance of α-MnO_2 Microspheres

以Ag片作催化剂在室温下制备了具有较高比表面积(177m2/g)的电化学电容器材料MnO2。XRD测试和SEM分析表明,所制备的MnO2为纳米纤维组成的仙人球状微球结构的α-MnO2。交流阻抗、循环伏安、恒流充放电和循环寿命等电化学测试均表明,所合成的α-MnO2微球在1mol/LNa2SO4水溶液中具有良好的电化学电容性能,单电极比电容可达187.1F/g,经1000次循环后电极容量仍保持在90%以上。

MnO2 with a high surface area of 177 m2/g as electrode for electrochemical capacitor was prepared with Ag foil as the catalyst at room temperature. The results of XRD and SEM showed that the MnO2 is α-MnO2 microspheres with cactus-like morphology composed of nanofibres. AC impedances, cyclic voltammetry and constant current charge-discharge tests indicated that α-MnO2 microspheres had an excellent electrochemical capacitance with the highest capacitance of 187. 1 F/g and retained 90% of the initial capacity over 1 000 cycles within the potential range of 0-0. 8 V versus SCE in 1 mol/L Na2SO4.