VOCs Sensing Property of Graphene Oxide Thin Film by Reduction Rate

Abstract

We demonstrate a combinatorial graphene oxide (GO) and reduced graphene oxide (rGO) thin film sensor fabricated by spin coating and dip casting method. Thermal treatment was followed to convert graphene oxide into reduced graphene oxide at different temperatures. 100ppm of evaporated methanol was utilized to examine the resistance profile of graphene oxide thin film and reduced graphene oxide thin film. Crystalline phase of GO and rGO were characterized by XRD. Surface roughness was observed by FE-SEM. Obvious opposite sensing property of GO and rGO were observed according to drying conditions.It was attributed to the change in number of radicals and type attached to the edge and surface of graphene oxide during reduction. Authors suggest that control of reduction rate by thermal treatment would be the one of the readiest approaches to enhance the selectivity of gas sensing in terms of direction of reaction.