三维石墨烯/二氧化锰复合材料的制备及其电化学性能
首发时间:2018-07-16
摘要:以氧化石墨烯(GO)、二氧化锰(MnO2)为原料,通过水热合成、冷冻干燥、高温活化制备出三维石墨烯/二氧化锰复合材料(3DG/MnO2),通过扫描电子显微镜(SEM)和X-射线衍射(XRD)对材料的结构和形貌进行了表征。石墨烯和二氧化锰有效复合,减少了二氧化锰粒子间的团聚和石墨烯片层间的堆叠,呈多孔三维网络结构。以制备出的三维石墨烯/二氧化锰复合材料为电极材料,组装锂离子电池。采用恒流充放电、循环伏安(CV)和交流阻抗(EIS)等对其电化学性能进行测试。在0.1 A/g电流密度下放电比容量达1142.4 mAh/g;在1 A/g电流密度下循环100次后,其容量保持率为85.3%。三维石墨烯/二氧化锰复合材料弥补了单一材料的缺点,在一定程度上提高了电极材料的电化学性能,是一种较理想的储能材料。
关键词: 石墨烯 二氧化锰 复合材料 锂离子电池 电化学性能
For information in English, please click here
Preparation and Electrochemical Performance of 3D Graphene/Manganese Bioxide Composites
Abstract:Three-dimensional (3D) graphene/manganese bioxide composites (3DG/MnO2) were prepared by hydrothermal reaction, followed by freeze-drying and high temperature activation process with graphene oxide (GO) and manganese bioxide as raw materials. The structure and morphology of the materials were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The combination of graphene and manganese oxide effectively reduces the agglomeration of manganese oxide particles and graphene presenting the 3D networks with porous structure. Lithium ion battery was assembled using this composite as electrode material. The electrochemical performance was measured by constant current charge and discharge, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The specific discharge capacity at current density of 0.1 A/g can reaches 1142.4 mAh/g, and after 100 cycles at current density of 1 A/g, the capacity retention rate is 85.3%. 3DG/MnO2 material shows more excellent electrochemical performance than graphene or MnO2, becoming an ideal electrode material for energy storage devices.
Keywords: graphene manganese bioxide composite materials lithium-ion battery electrochemical performance
引用
No.****
动态公开评议
共计0人参与
勘误表
三维石墨烯/二氧化锰复合材料的制备及其电化学性能
评论
全部评论