Highly sensitive sensors based on quasi-2D rGO/SnS2 hybrid for rapid detection of NO2 gas

Abstract

Abstract Nitrogen dioxide (NO2) sensing is important in terms of the agriculture development and healthcare monitoring. However, relatively poor recovery kinetics at a low temperature is still a problem for NO2 sensing and remains to be solved. In this work, we combine the excellent sensing properties and gas adsorption capacity of two- dimensional (2D) tin disulfide (SnS2) hexagonal nanoflakes with the beneficial electrical properties of graphene to build high-performance NO2 sensors by a simple and low-cost method. We found that the sensors based on the quasi-2D rGO-SnS2 hybrids exhibited exclusive selectivity towards NO2. The presence of rGO in hybrids decreased optimal working temperature effectively. Sensors based on 0.8% rGO-SnS2 (G-SS) show almost an order of magnitude increase in response (32) compared to pristine SnS2 (3.5). Especially, the response/recovery time is 50/48\u2009s, respectively, demonstrating the favorable response/recovery kinetics of sensors. Such significant features can be attributed to the synergistic effect of the quasi-2D G-SS hybrid and the local heterojunctions in the interface between SnS2 and rGO.