Sub-ppm level NO2 sensor with sulfur doped graphene

High sensitive NO2 sensors working at different temperatures using sulfur doped graphene were announced in this paper. The graphene was doped by introducing hydrogen sulfide gas flow as sulfur source at 1000°C in CVD after its transfer on a Si substrate with 300 nm thick SiO2 layer through PMMA coating method. The sensitivity of our S-doped graphene (SG) sensors varied with temperature from 70°C to 150°C. Although the sensitivity was not the best at 150°C, it still distinguished itself with shortest recovery time and the estimated detection limit of 50 ppb, which revealing a potential use in further detection of NO2 with low cost and high sensitivity.