Ethanol detection using composite based on reduced graphene oxide and CuO hierarchical structure under wet atmosphere

Abstract

Semiconductor metal oxides have been used for detecting volatile organic compounds (VOCs). However, these materials present a poor performance in humidity. Here, we report the effect of reduced graphene oxide (RGO) on the ethanol-sensing of CuO under dry and in the relative humidity range of 36–90%. For this purpose, RGO-CuO composites and CuO were synthesized by a one-step microwave-assisted synthesis. The VOCs sensing were performed at the range of 150–350 °C to acetone, benzene, ethanol, methanol, and m-xylene. The RGO-CuO composites exhibited enhanced ethanol sensing when compared with pure CuO at the optimal operating temperature of 250 °C. In addition, the optimal RGO content resulted in an enhanced selectivity and high sensitivity compared to pure CuO. The enhanced ethanol sensing performance of RGO-CuO was attributed to the RGO/CuO heterojunction. Thus, the combination of RGO and p-type CuO semiconductor can be a promising for VOCs detection under wet conditions.