Gamma radiation effects on graphite

Full text: Graphite is an allotropic form of carbon, comprising several stacked layers of graphene, where the carbon atoms are tightly packed into a two-dimensional network of successive hexagons. Compared to carbon nanotubes, graphenes attract attention because of their outstanding mechanical and electrical properties. Exfoliation of graphite can be obtained by chemical or physical treatments. The radiation effect on matter causes changes in the structure, both microscopic and macroscopically. Therefore, we wish to verify the effect of gamma irradiation in the structure of graphite, seeking an alternative route for obtaining graphene with a high degree of purity. Graphite flakes were irradiated under 370 kGy and 740 kGy. Raman spectroscopy, UV-visible spectroscopy, scanning electron microscopy and X-ray diffraction were used to evaluate the systems before and after irradiation. Significant changes in the structure of the flakes were observed both in SEM images as the results obtained with x-ray diffraction. References: [1] FENG, Y. et al. The effect of gamma ray irradiation on the structure of graphite and multi-walled carbon nanotubes. Carbon, v. 60, p. 186-192, 2013. [2] NOVOSELOV, K. S. et al. Electric Field effect in atomically thin carbon films. Science, v.306, n.5696, p. 666-669, 2004. [3] WOODS, R. J.; PIKAEV, A. K. Applied radiation chemistry: radiation processing. New York: John Wiley & Sons, Inc., 1994. (author)