Active edge effect of pothole-rich WO3 nanosheets for enhancing dimethyl trisulfide gas sensing performance

The gas sensing mechanism of metal oxides has always been the research focus in the field of gas sensors. Herein, a novel gas sensing mechanism based on the active edge effect was proposed to account for the difference in gas sensing performance between pothole-rich WO 3 and non-porous WO 3 nanosheets. The gas sensor based on pothole-rich WO 3 exhibited a higher response (9.5) than non-porous WO 3 (6.8) when exposed to 500 ppb C 2 H 6 S 3 , which could be ascribed to the active edge sites on the pothole-rich WO 3 nanosheets. DFT calculations and XPS confirmed that the edge sites showed higher adsorption energy and more charge transfer for C 2 H 6 S 3 gas, and W-S bond was formed at the edge site due to the strong chemical adsorption. • Thin pothole-rich WO 3 nanosheets and thick non-porous WO 3 nanosheets had been synthesized to detect ppb-level C 2 H 6 S 3 . • The sensor based on pothole-rich WO 3 exhibited ultra-high sensitivity and high selectivity towards ppb-lever C 2 H 6 S 3 . • DFT calculation and XPS characterization results confirmed the strong interaction of C 2 H 6 S 3 at the W site and the formation of W-S. • The abundant active edge sites in pothole-rich WO 3 nanosheets enhance the gas sensitive reaction.