摘要:
采用水性溶液为电解液,在石墨烯表面用恒电位法依次制备二氧化锰和聚3,4-乙烯二氧噻吩层,得到石墨烯/二氧化锰/聚3,4-乙烯二氧噻吩三相复合电极.扫描电镜表征三相复合电极的形貌特征及复合结构;通过恒流充放电、循环伏安、交流阻抗等电化学测试方法研究三相复合电极的电化学性能.结果表明,石墨烯呈现独有的褶皱状结构,二氧化锰由不规则的纳米片交织而成,聚3,4-乙烯二氧噻吩由纳米范围粒子聚合而成,三相电极呈现层状复合结构;在1.0 A/g的充放电电流下得到的比容值为165 F/g,经过500次充放电循环后,容量保持率达到80%,具有较好的稳定性,同时,该三相复合电极还表现出很好的充放电可逆性和阻抗性能.%Three-phase composite electrode composed of graphene,manganese dioxide,and poly(3,4-ethylened-ioxythiophene)was obtained by potentiostatic method.The manganese dioxide and poly(3,4-ethylenedioxythio-phene)layers are prepared on the surface of graphene,with aqueous solution as electrode.The morphology characteristics and the composite structure of the three-phase composite electrode are characterized with scan-ning electron microscope (SEM).The electrochemical properties of composite electrode are measured by con-stant current charge-discharge,cyclic voltammetry,and alternating current impendence (AC impedance)meth-ods.The results show that the grapheme was special fold structure,the manganese dioxide was irregular nanosheets,the poly(3,4-ethylenedioxythiophene)was aggregated by nanoparticles,the three-phase composite electrode was layered composite structure.The specific volume was 1 65 F/g under 1.0 A/g charge-discharge current.The capacity maintains 80% after 500 charge-discharge cycles which show good stability.The three-phase composite electrode presents very good discharge reversibility and impedance-resistant.