MoS2-GO hybrid sensor: A discerning approach for detecting harmful H2S gas at room temperature

Abstract

The molybdenum disulfide (MoS2)- graphene oxide (GO) hybrids have fashioned by a clean hydrothermal route. Initially, two-dimensional GO sheets have synthesized using the modified Hummer’s method and intercalated into the MoS2 nanoparticles (NPs). The sophisticated characterizations comprising X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) analyzer, custom designed gas sensing set-up, etc. utilized for the analysis of as-prepared MoS2-GO (1 to 5 wt%) hybrids. The maximum sensor response exhibited by as-prepared MoS2-GO (3%) hybrid sensor was 39.16% towards 100 ppm hydrogen sulfide (H2S) gas at room temperature (RT, i.e., 28 °C) in a quickest response time (6.13 s) and least concentration of H2S detected was 1 ppm with response value 0.51%. This report investigated first time that as-prepared MoS2-GO (MG) hybrids with varied proportion of GO (1 to 5 wt%) demonstrated spectacularly improved gas sensing performance towards H2S at RT. The boosted gas sensing performance of MG hybrids could be attributed to the synergistic influence of constituents i.e., MoS2 NPs and GO sheets. An impedance spectroscopy has been exploited to study the interactions between H2S gas molecules and MG hybrid sensor surface.