부산대학교 도서관

Graphene is a single layer of graphite with hexagonal structure which have stacked layers. Graphene has recently been recognized by its researchers due to it have sp2 bonds in hexagonal lattice, the two-dimensional structure of a single atomic thickness, and its superior electrical, electrochemical, optical, thermal, mechanical properties and lightness. Liquid phase exfoliation (LPE) is the most promising method of graphene research to produce high quality graphene in the production of single or low layer graphene layers. In addition, LPE is an easy and inexpensive method as well as enables the production of higher capacity graphene. LPE method in the production of graphene is the use of surfactant mainly to make water suitable as a means of exfoliation. Furthermore, graphene adsorbable surfactants provide an effective charge by electrostatic repulsion to prevent the re-aggregation of graphene sheets, thus providing stabilization against the recombination of suspended graphene layers. Because 1,2-Dichlorobenzene or ortho-dichlorobenzene (O-DCB) is both effective as solvent for graphene synthesis, it is one of the best production of graphene by the liquid phase exfoliation method. In this study, graphite powders were mixed in an acid solution of [H.sub.2]S[O.sub.4] and HN[O.sub.3] for 12h. The resulting powder was washed with distilled water until a neutral pH was obtained and then subjected to thermal treatment to obtain expanded graphite. The resulting powder was then mixed in an ultrasonic homogenizer in a mixture of O-DCB for 2h using 50 % strength and then it was examined by Transmission electron microscope (TEM) and X-ray photoelectron spectroscopy (XPS). Keywords: Graphene, ortho-dichlorobenzene, Expanded Graphite, LPE.
1. INTRODUCTION Graphene is known as a surprising material in recent years due to its new features related to its two-dimensional structure (Monajjemi, 2017). Its intriguing properties such as high [...]