Effects of chemical and physical defects on the humidity sensitivity of graphene surface

Abstract

We investigate the effect of the chemical and physical defects on the humidity sensitivity of graphene. For this we apply reactive ion etching for physical defects and the poly(methyl methacrylate) (PMMA) coating for chemical defects to the CVD graphene. The tendency of humidity sensing is hardly found by the physical defects while the distinct changes are observed with chemical defects by control of the thickness and the coverage area of the PMMA on the graphene surface. The graphenes covered with thinner or smaller area of PMMA show an enhanced humidity sensitivity, indicating the possibility of H2O sensing. (C) 2017 Elsevier B.V. All rights reserved.