PtO2-decorated MoS2 ultrathin nanostructures for enhanced NH3 gas sensing properties

Recently, transition metal dichalcogenides (TMDs) have attracted much attention due to their high surface-to -volume ratio, various active edge sites, and adjustable bandgaps. However, in general, TMDs still exhibit low gas response and incomplete recovery. Surface modification is an effective way to facilitate the adsorption and desorption processes, thus enhancing the TMD gas sensor's sensing performance. In this study, a PtO2-decorated MoS(2 )nanostructure gas sensor was fabricated using a chemical reduction process. The result showed that the as -obtained nanostructures consist of accumulated ultrathin MoS2 nanosheets decorated with spherical PtO2 nanoparticles. The gas response of the as-obtained PtO2-decorated MoS2 gas sensor toward NH(3 )is remarkably high, with 450% upon 500 ppm NH3, which is almost 20 times higher than that of the pristine MoS2 nano -structure gas sensor in their optimal working conditions. The enhancement in gas sensing properties was attributed to the catalytic spillover effect of PtO2 nanoparticles as well as the formation of p-p heterojunction on the MoS2 surface.

Automated summary

In this study, a PtO2-decorated MoS2 nanostructure gas sensor was fabricated using a chemical reduction process. The gas response of the as-obtained PtO2-decorated MoS2 gas sensor toward NH3 is remarkably high, almost 20 times higher than that of the pristine MoS2 nano-structure gas sensor.