【摘 要】
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A composite material composed of Graphene and Mn3O4 nanoparticles (GM composite) was prepared by microwave-assisted in-situ synthesis of Mn3O4 nanoparticles on the graphene nanosheets.SEM and TEM imag
【机 构】
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School of Material and Energy,Guangdong University of Technology,Guangzhou 510006,China
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A composite material composed of Graphene and Mn3O4 nanoparticles (GM composite) was prepared by microwave-assisted in-situ synthesis of Mn3O4 nanoparticles on the graphene nanosheets.SEM and TEM images showed that Mn2O4 nanoparti-cles with size of 20-50 nm are uniformly distributed on the graphene nanosheets.Compared to the pure Mn3O4,the the excellent contact between the graphene and Mn2O4 nanoparticles helps to decrease the resistance and improve the cycle life of the supercapaci-tor.The GM composite exhibits good electrochemical performance with a maximum specific capacitance of 296.8 F g-1 at the charge/discharge current density of 1 A g-1 with 5 M NaOH as electrolyte and a high energy density up to32.9 W h kg-1 at the power density of 800 W kg-1.After 5000th cycling,a high level retaining specific capacitance of 294.3 F g-1 is obtained which still retained 99.2% of the initial capacity and the equivalent series resistance of the GM composite system is only 0.39 Ω.GM composite shows a large capacity,good cyclicity and reversibility and is promising electrode material for supercapacitor application.
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