一步合成还原氧化石墨烯/MnO2复合材料及其电化学性能

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%。

One-step Synthesis and Electrochemical Properties of Reduced Graphene Oxide/MnO2 Composites

Reduced graphene oxide/MnO₂ (RGO/M) composites were successfully prepared via one-step hydrothermal routine, in which graphene oxide serviced as the oxidant and Mn²⁺ 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 microscope (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 capacitance retention of 98% after 500 cycles.