Graphene and graphite are two widely studied carbon materials. Due to their particular structures, physical and chemical properties, graphene and graphite have been used in a variety of fields. Surface modification of graphene and graphite is an important way to improve their properties and thus makes a better contribution in various applications. After modification, different types of carbon are formed on the surfaces of graphene and graphite. X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) are two surface sensitive techniques, which provide the surface chemical composition and detailed molecular information on the surface of a sample. A combination of the two techniques can give a better understanding of the surfaces of graphene and graphite.

In this thesis, we did a fundamental study of the graphene and graphite surfaces by XPS and ToF-SIMS as well as their surface modifications and potential environmental applications. Clean graphene and graphite surfaces were obtained by annealing at high temperature in an ultra-high vacuum chamber. XPS and ToF-SIMS spectra of clean graphene and different types of graphite (i.e., highly oriented pyrolytic graphite (HOPG), sputtered HOPG, graphite powder, hydrogenated graphite powder and graphite oxide powder) were compared and possible fragmentation mechanisms of selected ions in the ToF-SIMS spectra were proposed. In addition, the reactions between graphite oxide powder and sulfur dioxide (SO2) and ammonia (NH3) gases were carried out and the products were analyzed by XPS and ToF-SIMS. The fundamental understanding of the reaction mechanisms may lead to the development of a novel method for the removal of SO2 and NH3.