Enhancement of room temperature ethanol sensing behavior of PbS–SnS2 nanocomposite by Au decoration

Abstract

Resistive-based gas sensors generally work at high temperatures, and this leads to some limitations in their applications in remote areas or low power consumption electronic devices. Realization of room temperature gas sensors can be an excellent strategy to significantly decrease the power consumption of these kinds of gas sensors. Herein, we prepared pristine and Au-decorated PbS–SnS2 nanocomposite for ethanol sensing at room temperature. In order to find the optimal amount of Au-decoration, different amounts of Au (0.5, 1, and 1.5 wt%) were added to PbS–SnS2 nanocomposite. Based on the ethanol sensing studies, it was found that the sensor with 1 wt% Au had the highest sensing performance towards ethanol. The optimal gas sensor showed the highest response to ethanol gas, and fast sensor dynamics (less than 80 s) at room temperature. Enhanced sensing capacity of the optimized gas sensor was related to the formation of Au-metal sulfide heterojunctions and catalytic effect of Au towards ethanol. This research demonstrates the promising effects of noble metal decoration on metal sulfides for room temperate sensing applications and can be extended to similar systems.