Co_3O_4/CoO/Co/石墨复合材料的制备及其电容性能研究

Synthesis and Capacitance Performance of Co_3O_4/CoO/Co/graphite Composite

以葡萄糖为前驱物,采用水热法合成了胶态碳球,然后利用胶态碳球制备了Co3O4/CoO/Co/石墨复合材料.此复合材料与其它研究者采用类似方法制备的物质相比具有完全不同的结构,它们是由多层不同物质组成的球形结构,其最外层是Co3O4,第二层是CoO,第三层是Co,最里面一层是石墨.采用循环伏安和恒电流充放电等方法对Co3O4/CoO/Co/石墨的电化学性能进行了测试.研究表明:该材料的电容行为是由氧化还原反应所产生的法拉第赝电容和双电层电容组成,其比电容为25.2 F g-1,比纯Co3O4的低,但电势窗口为-1.0～0.46 V,比纯Co3O4的大.

Colloidal carbon spheres were prepared using glucose as precursor by hydrothermal synthetic route,and then Co3O4/CoO/Co/graphite composites are synthesized with colloidal carbon spheres.The composites possess different structures in comparison to materials prepared by other researchers with similar method.They consist of multilayer materials with spherical structures.The first,second,third and inner layer are Co3O4,CoO,Co and graphite,respectively.Electrochemical property of Co3O4/CoO/Co/graphite was studied by cyclic voltammetry and constant current charge-discharge.The results showed that capacitive performance of the composites results from pseudo-capacitance caused by redox reactions and electric dou-ble-layer capacitance.The specific capacitance of the material is 25.2 F？g-1,which is lower than that of Co3O4.However,the potential windows is-1.0～0.46 V,which is higher than that of Co3O4.