MMNi Zn MnCo2O4氧化石墨烯超电容性能的研究.docx

M(M=Ni,Zn,Mn)C0204／氧化石墨烯超电容性能的研究 A study on M(M=Ni，Zn，Mn)C0204／Graphene Oxide Electrode Materials for Supercapacitors Abstract Increasing energy demand，uncertainties in energy supply and global wanning necessitate the development of sustainable energy converSion and energy storage systems， such as solar cells，batteries，fuel cells and supercapacitors．Supercapacitors(SCs)are one of the most promising high performance energy storage devices and are also referred to as electrochemical capacitors or ultraeapacitors．SCs exhibit significant characteristics such as， low equivalent series resistance，fast power delivery or uptake，high-power density，high cycle efficiency and long life cycle． Generally，the electrode materials of supercapacitors are of three types，carbon materials， conducting polymers and transition metal oxides．Carbon materials have outstanding electrical properties，long life-cycles and great mechanical properties，but small double layer capacitance．Conducting polymers are inexpensive and flexible，but have poor cyclability． Transition metal oxide materials have high specific capacitance but poor electronic conductivity，and in some cases they are expensive．The three kind materials have their own advantages and disadvantages．Therefore，fabrication of binary or ternary composites with a combined and balanced merit of different materials is an effective way to obtain electrode materials、Ⅳith 11igh supercapacitive performance．Graphene is an intriguing two-dimensional carbon material and emerges as an excellent electrode material for EDLC because of its high electrical conductivity and theoretical high surface area(2630 m2 g-1)．Among the transition metal oxides，nickel and cobalt oxides 0NliC0204)are considered as one of the most promising pseudocapacitor electrode materials due to its abundance，low cost，environmental harmlessness and high electrochemical performance．Hence fabrication of metal oxides (NiC0204)and graphene oxide(GO)composites as electrode materials