4-30 Charge State Effect on Raman Spectra of Graphene Irradiated with Highly Charged Ion

Graphene is two dimensional materials which is made of honeycombed carbon atoms. It attracts extensiveinterests for its wonderful characteristics that make the graphene a potential candidate in fields of microelectronicsproduction, molecule detection, desalination and DNA sequencing. Highly charged ion (HCI) has huge potentialenergy for peeling off electrons. When interacting with solid surface, the HCI distorted the solid lattice via potentialdeposition and then the nanostructures were formed on the solid surface. The HCI was expected as a tool for surfacemodification. In this work, HOPG and grapheme were irradiated with Xeq+ and Arq+ ions. The typical Ramanspectra of graphene and HOPG irradiated with highly charged ions were shown in Fig. 1. The D peak appeared at1 335 cm??1 on the spectra of graphene irradiated with highly charged ions. The intensity of D peak increased withfluence. The ratio of intensity of D peak to that of G peak varied with fluence in Fig. 2. The ratio rose linearlywith the square root of fluence when fluence was low. The ratio saturated when the irradiation fluence was high.The critical fluence depended on the charge state of ion. The higher charge state it was, the lower critical fluenceit would be.