二氧化锰/球形活性炭复合材料在有机系超级电容器中的应用

以Mn(NO3)2和中间相炭微球基球形活性炭（MSAC）为原料，采用热分解的方法成功制备了一种新型超级电容器用MnO2/MSAC球形复合材料。 通过X射线衍射、扫描电子显微镜和透射电子显微镜对比分析了该复合材料的结构和形貌，并采用循环伏安、恒流充放电、电化学阻抗（EIS）、循环充放电研究了电极的电化学性能。 结果表明，MnO2/MSAC球形复合物中的MnO2粒径为100~160 nm；在1 mol/L的LiPF6/(DMC+EC)（EC：乙烯碳酸酯；DMC：碳酸二甲酯) 有机电解液中MnO2/MSAC复合材料所组装的电容器的工作电压可达3.0 V，在0.002 A/cm2电流密度下，MnO2/MSAC球形复合材料的电容器和单纯MSAC材料的电容器的首次循环比容量分别为186和167 F/g，在循环过程中，MnO2/MSAC球形复合材料的电容器循环200次后充放电的库仑效率基本保持在95%以上。 此外，MnO2/MSAC球形复合材料的充放电曲线表现出典型的电容行为；循环伏安曲线也表现出良好矩型特征，同时具有较高的能量密度和良好的功率性能。

Application of Mesocarbon Microbead/Manganese Oxide Composite Electrodes in Supercapacitor

A novel MnO2/MSAC(micro-spherical activated carbon base on mesocarbon microbead) composite, which might be used as an electrode material in electrochemical capacitor, was prepared by dispersing thermally decomposed MnO2 from manganese nitrates on MSAC. The morphology and crystal structure of the composite were investigated by scanning electron microscopy(SEM)， transmission electron microscope(TEM) and X-ray diffraction(XRD), respectively. The electrochemical properties of the electrode were studied by cyclic voltammetry(CV), galvanostatic charge-discharge, and electrochemical impedance spectroscopy(EIS) in 1.0 mol/L LiPF6. Our results showed that the MnO2 particles dispersed on MSAC have particle size in the range of 100~160 nm, the initial specific capacitance of the MSAC/MnO2 and single MSAC electrode are 186 F/g and 167 F/g respectively at 2×10-3 A/cm2 current density. The Coulombic efficiency of MnO2/MSAC spherical compound materials capacitor remained above 95% after 200 charge and discharge cycles. In addition, the charge-discharge curve of the MSAC/MnO2 electrode showed typical capacitive behavior with a good linearity, and the CV curve also showed good rectangular features, high energy density and good power performance.