Revealing ppb order NO2 adsorption capability of 2D/0D p-p heterojunctions based on Sb/SnS nanocomposite

Abstract

Highly sensitive p-p heterojunction-based gas sensors have a lot of promise in the field of trace gas detection. The ability to detect ppb-order NO2 reliably is critical for environmental monitoring, yet it is still a difficulty. In this work, we demonstrate the ultrasensitive p-p heterostructures based on Sb/SnS novel architect to detect the ppb order of NO2 gas at room temperature. The incorporation of 0D SnS QDs in Sb sheet enhanced the gas-capturing capability of nanomaterial. SnS-doped Sb outperformed state-of-art Sb-based NO2 sensor with a huge response of 0.13 at 75 ppb of NO2 and a limit of detection (LOD) of 15.2 ppb with an average power consumption of 1.49 nW. In comparison to other gases, the selectivity results show that Sb/SnS have the highest sensor response (1.73 ppm−1) to NO2. The enhanced NO2 gas sensing mechanism of Sb/SnS QDs is explained briefly, which is due to the enrichment of its surface charge carrier on the surface of the Sb/SnS sample as confirmed by the DFT simulations results. Our findings might be used to develop alternative p-p heterojunction-based novel architects for gas sensors and other applications.