化学还原石墨烯薄膜的制备及结构表征

Preparation and Structural Characterization of Chemically Reduced Graphene Films

以天然鳞片石墨为原材料,采用Hummers法成功制备了氧化石墨,并采用化学还原方法制备石墨烯薄膜材料,分别应用X射线衍射(XRD)、能谱分析(EDS)、拉曼光谱分析(Raman)、傅里叶变换红外光谱(FTIR)和扫描电镜(SEM)对氧化石墨和化学还原石墨烯薄膜的性能、结构和形貌进行了表征。实验结果表明,通过控制溶液的pH值为10可防止石墨烯团聚,石墨烯溶液的分散性非常好,碳氧比达到了8.8∶1,扫描电镜图片观察到了较薄的片层。通过XRD图谱可以看出,石墨烯薄膜比原始石墨的层间距变大。拉曼光谱表明,石墨烯薄膜相对氧化石墨的ID/IG值更大,样品在还原的过程中无序度增加。石墨烯薄膜的微观结构研究为其在超级电容器电极或重金属废水过滤膜等方面的应用提供了理论基础。

Based on the Hummers methods, the graphite oxide was synthesized from natural flake graphite. Then the graphene films were obtained by the chemical reduction method. Finally, the graphite oxide and graphene were analyzed by X-ray diffraction（XRD）, energy dispersive spectrometer（EDS）, Raman spectrum analyzer （Raman）, FTIR spectra and scanning electron microscope （SEM）. The aboved analysis showed that the hydrophobic graphite or graphene films dispersed homogeneously in water when the pH was approximately 10. The graphene films performed satisfactorily, and had a small thickness confirmed by SEM as well as a ratio of C to O near 8.8. X-ray diffraction resuits showed that layer spacing of graphene films became larger than the original graphite. Raman results showed that ID/IG of graphene films was larger than graphite oxide, and the degree of sample disorder increased, The present study on microstructure of graphene films will promote its further application as supereapacitor electrode or membranes for heavy metal-containing wastewater purification.