一步合成还原氧化石墨烯/MnO_2复合材料及其电化学性能

One-step Synthesis and Electrochemical Properties of Reduced Graphene Oxide/MnO_2 Composites

通过水热法,利用氧化石墨烯(GO)和二价锰盐,一步合成了还原氧化石墨烯/MnO2(RGO/M)复合电极材料。采用X射线衍射(XRD)、X射线光电子能谱(XPS)、拉曼光谱(RS)、傅里叶红外光谱(FTIR)和场发射扫描电镜(FESEM)等测试电极材料的物性,通过循环伏安、交流阻抗和恒流充放电等方法研究电极材料的电化学性能。结果表明,在一定水热反应条件下,通过控制GO与二价锰盐配比,可以调节RGO/M的结构及其电化学性能。在1 A/g电流密度下,所得RGO/M复合电极的比电容可达277 F/g,经过500次循环后,保持率达到98%。

Reduced graphene oxide/MnO2 （RGO/M） composites were successfully prepared via one-step hydrothermal routine, in which graphene oxide serviced as the oxidant and Mn^2＋ as the reducer. The morphology and microstructure of the nanocomposites were characterized by X-ray diffraction （XRD） analysis, X-ray Photoelectron Spectroscope （XPS）, Raman spectra （RS）, Fourier transform infrared （FTIR） spectroscope and field emission scanning electron mi- croscope （FESEM）. In addition, the electrochemical properties of the composite were evaluated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy techniques for supercapacitor applications The results indicate that the RGO/M composites displayed controllable specific capacitance in acidic electrolytes by adjusting the molar ratio of GO to manganous chloride at a specific hydrothermal reaction condition. In the optimal case, a specific capacitance of 277 F/g can be obtained in 1 mol/L H2SO4 at a scan current density of 1 A/g, with a ca- pacitance retention of 98% after 500 cycles.