酸化辅助Hummers法制备高性能石墨烯

以天然鳞片石墨为原料, 采用Hummers法制备氧化石墨, 制得的氧化石墨经超声波振荡得到氧化石墨烯, 在还原剂水合肼作用下加热回流制得石墨烯纳米材料。采用X射线衍射仪与拉曼光谱对天然石墨、氧化石墨和石墨烯进行表征, 透射电子显微镜观察石墨烯样品形貌, 并使用三电极体系进行循环伏安法测试, 分析石墨烯材料的电化学性能, 结果表明, 石墨烯为褶皱状薄层结构, 衍射峰宽化且强度较弱, 完整度介于石墨和氧化石墨之间, 堆垛取向为无序的石墨结构。石墨烯的双电层电流远大于XC-72导电炭黑的双电层电流, 相对于XC-72, 石墨烯具有更高的电化学活性面积。

Preparation of High Performance Graphene by Acidification-assisted Hummers Method

Graphite oxide was firstly prepared by using Hummers method with natural flake graphite, with which graphene oxide was synthesized by supersonic oscillation. In the presence of reductant hydrazine hydrate, graphene oxide was then reduced to graphene by heating reflux. The structure of graphite, graphite oxide and graphene were all characterized by X-ray diffractometry and Raman spectra, the morphology of graphene was observed with a transmission electron microscope, and the electrochemical properties of graphene were investigated by cyclic voltammetry in a three electrode system. It can be known from the results that graphene with a thin folded structure and broadened diffraction peaks with weaker intensity, has the integrity between graphite and graphite oxide and a disorder graphite structure with the stacking orientation. The double-layer current of graphene is far larger than that of conductive carbon black XC-72, indicating a higher electrochemical active surface for graphene.