Reduced graphene oxide-SnO2 nanocomposite thin film based CNG/PNG sensor

•Low temperature CNG/PNG sensor developed using reduced graphene oxide-SnO2 thin film.•Sensing response of 60% obtained at low operating temperature of 90° C.•Exhibits fast response and recovery with good selectivity.

A low temperature operated, highly sensitive and selective CNG/PNG sensor has been developed in the present work using reduced graphene oxide (rGO)-tin oxide (SnO2) nanocomposite thin film prepared via chemical route. The maximum sensing response of 60% was observed at a low operating temperature of 90 °C towards 1000 ppm of CNG/PNG. Concentration of rGO is optimised in the nanocomposite sensing layer to achieve the enhanced sensing response. The enhancement in sensing response characteristics is attributed to the increased surface to volume ratio of the SnO2 nanoparticles due to incorporation of rGO sheet in nanocomposite sensing layer besides providing the short conduction path across the SnO2 nanoparticles. The obtained results on sensing response and the origin of sensing mechanism are presented in detail in this communication.