Cuprous oxide nanowires/nanoparticles decorated on reduced graphene oxide nanosheets: Sensitive and selective H2S detection at low temperature

Abstract Hydrogen sulfide (H2S) is a colorless gas with a smell of rotten eggs which poses great threat on human health and environmental protection. Traditional metal oxide based H2S sensors always suffer from undesirable selectivity and elevated operation temperature. To overcome these obstacles, in this report cuprous oxide nanowires/nanoparticles (Cu2O) anchored onto reduced graphene oxide nanosheets (rGO) were prepared to serve as the sensing layer. Multiple characterization techniques such as SEM, TEM, FTIR, and XRD were utilized to explore the sensor performance toward H2S gas. Compared to the partial recovery at 25 °C, the prepared rGO/Cu2O sensor showed a response of 20% toward 1 ppm H2S at 40 °C, together with full restoration, excellent repeatability, long-term stability and selectivity. Favorable film porosity, highly conductive rGO nanosheets and nanometer size effect of Cu2O materials were responsible for these inspiring results, paving the avenue for future trace H2S detection in the aspects of higher sensitivity and lower power-consumption.