自支撑GN/MnO2复合材料的制备及其 电容性能研究
Preparation of free-standing graphene/MnO2 composite material and its capacitance properties

本文通过水热辅助真空冻干法制备得到了可以自支撑的石墨烯/二氧化锰（GN/MnO2）复合材料，利用X射线衍射仪（XRD）和扫描电子显微镜（SEM）分别对复合材料结构与形貌进行表征，并以复合材料为工作电极，组装成对称电容器，探究反应物质量比与电解液对材料电化学性能的影响. 结果表明：在KOH电解液中，复合材料的比电容最大；当反应物质量比为1:4时，该复合材料比电容可以达到224 F/g（电流密度为1 A/g）.
A free-standing graphene/MnO2 composite material has been prepared through a simple hydrothermal method, followed by freeze-dried in vacuum treatment. The structure and morphology of the composite were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effects of mass ratio of reactants and electrolyte on the electrochemical properties of the materials were investigated. The results show that the specific capacitance of the composite is the largest in KOH electrolyte. In addition, the specific capacitance of the composite material can reach 224 F/g (the current density is 1 A/g) when the mass ratio of reactants is 1: 4