Highly selective and sensitive MoS2 nano-sensor for H2S detection

Facile hydrothermal route was employed to prepare MoS2 nanoparticles (NPs) on the glass substrates at low temperature. MoS2 NPs were crystallized into hexagonal lattice. The MoS2 NPs have superior specific surface area (4.33 m2/g). The gas sensing performance of MoS2 NPs nano-sensors were examined towards distinctive gases (H2S, O2, CO, NH3, NO2 and SO2) and operating temperatures (28–100 °C). MoS2 NPs synthesized at 120 °C for 4 h exhibited excellent gas sensing performance. MoS2 NPs nano-sensor delivers outstanding selectivity towards H2S gas. At room temperature, the highest response achieved was 24% towards 100 ppm H2S. MoS2 NPs nano-sensor quickly responds (in 0.28 s) to target H2S gas and speedily recovers (in 15.48 s) to original state. MoS2 NPs nano-sensor has detected the least concentration of the H2S gas was 1 ppm. Impedance measurements were employed to study the adsorption-desorption interaction between the reducing H2S gas molecules and MoS2 NPs nano-sensor surface. The room temperature performance and speedy response-recovery of the MoS2 NPs nano-sensor comprises it in the list of outstanding candidates for H2S gas sensing applications.