Structural Evolution during the Oxidation Process of Graphite
FAN Bing-Bing1,2, GUO Huan-Huan1, ZHANG Rui1,3**, JIA Yu2, SHI Chun-Yan1
1School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001 2School of Physics and Engineering, Zhengzhou University, Zhengzhou 450001 3Laboratory of Aeronautical Composites, Zhengzhou Institute of Aeronautical Industry Management, Zhengzhou 450046
Abstract:The structural evolution during the oxidation process of graphite by a modified Hummers method is investigated. The graphite oxide (GO) composition, disorder parameter, and structures are confirmed by means of x-ray diffraction, Fourier transform infrared spectroscopy, Raman, and scanning electron microscope techniques. Results show that: Hydroxyl, carboxyl and ether groups are present in the low-temperature oxide (at 0°C); and the degree of oxidation is increased with a longer oxidation time. The middle-temperature oxidation (35°C) is a transitory stage with a slight change to the GO structures. While for the high-temperature oxidation (95°C), the hydroxyl, carboxyl and epoxide functional groups are largely originated on the GO flakes. Hydroxyl groups are transformed into more epoxide groups with longer oxidation time, and at the same time, ether groups are eliminated, leading to defects (such as holes) on the GO flakes.
. [J]. 中国物理快报, 2014, 31(07): 78102-078102.
FAN Bing-Bing, GUO Huan-Huan, ZHANG Rui, JIA Yu, SHI Chun-Yan. Structural Evolution during the Oxidation Process of Graphite. Chin. Phys. Lett., 2014, 31(07): 78102-078102.