Reduced graphene oxide obtained using the spray pyrolysis technique for gas sensing

Abstract

Graphene oxide films were formed using the ultrasonic spray coating method and studied with micro-Raman spectroscopy, atomic force microscopy, and electrical dynamic response of resistance measurements. The effect of different gases (water vapor, ethanol, acetone, ammonia, and isopropyl) on the dynamic response of resistance of the Au / graphene oxide / Au structure has been studied. The dynamic response shows that adsorption of all the mentioned gases results in an increase in the resistance. For ethanol, acetone, and isopropyl, the adsorption and desorption cycles are almost identical. At the same time, in the case of water vapor and ammonia, the cycle of desorption is very weak, especially for the former, which attests to different mechanisms of adsorption/desorption processes regarding ethanol, acetone, and isopropyl. The mechanisms of the studied vapors' adsorption/desorption are proposed.