Li2M4O9-石墨烯复合材料的制备及其电化学性能研究

采用溶胶凝胶法制备Li2M4O9，将其与氧化石墨烯在不同溶剂中进行溶剂热反应，以制备Li2M4O9墨烯复合材料，通过x射线衍射（XRD）、扫描电镜（SEM）进行表征，并对其进行一系列的电化学性能测试，包括充放电、循环伏安、循环效率、循环性能和交流阻抗测试。Li2M4O9-墨烯复合材料首次放电比容量由144．6mAh/gr提高至212．8mAh／g，50次充放电循环后，库仑效率保持在95％以上，电化学性得到提高。

Study on Preparation and Electrochemical Performances of Li2M4O9-graphene Composite Materials

Li2M4O9 was prepared solvothermal method in different by sol-gel method. The prepared Li2M4O9 compounded with GO by solvents. The product was characterized by X-ray diffraction （XRD） and scanning electron microscope （SEM）. A series of electrochemical capacitance performances were tested, including charge/discharge, cyclic vohammetry, coulombic efficiency, cycling ability and electrochemical impedance spectroscopy. The results indicated that the discharge capacity of Li2Mn4O9- GO composite was enhanced comparison with Li2Mn409. The discharge capacity was enhanced from 144.6 to 212.8 mAh/g and the coulumbic efficiency retained with 95% after 50 cycles. In general, the electrochemical performances were improved.