石墨烯/二氧化锰复合材料的制备及其电化学性能

Synthesis and electrochemical properties of graphene/MnO₂ composites

摘要: 通过水热法在160℃条件下成功制备了手风琴状石墨烯/MnO₂复合材料.通过场发射扫描电镜、透射电镜、X射线衍射、X射线能量色散谱、BET法以及拉曼光谱对材料进行表征.结果表明,手风琴状二氧化锰与层状石墨烯之间具有十分高效的贴合,这种创新性设计有效地利用了石墨烯的高电导率、大比表面积以及二氧化锰的优秀赝电容行为.电化学测试结果给出在0.2 A·g^-1时,样品的比电容高达138 F·g^-1,数倍增强于单独的二氧化锰或石墨烯样品.

Abstract: Accordion-like MnO₂-coated graphene composites were successfully prepared by a facile hydrothermal method at 160℃. The as-products were characterized by field emission scanning electron microscopy, transmission electron microscopy, X-ray dif-fraction, energy dispersive spectrometry, BET and Raman spectroscopy. The high capacitance of 138 F·g^-1 at 0.2 A·g^-1 is achieved with MnO₂/graphene composites as a supercapacitor electrode, much higher than that of a single MnO₂ or graphene electrode. The ex-cellent electrochemical performance is attributed to the uniform MnO₂ nanosheet morphology, large surface area of graphene and stable chemical bonding of MnO₂ on the graphene substrate.