Photochemical oxidation of CVD-grown single layer graphene.

CVD-grown single layer graphene undergoes rapid photochemical oxidation in the presence of ultraviolet light and oxygen. The oxidation results in a homogeneous decay of the graphitic material; no nanoscale line cracks or pits were observed with an atomic force microscope. The conductivity of the graphene film decreases with an increasing degree of oxidation. It is crucial to understand and enhance the photochemical stability of graphene for its long term use as a transparent conducting material.