MXene/WS2 hybrids for visible-light-activated NO2 sensing at room temperature

Abstract

Optoelectronic gas sensors based on two-dimensional (2D) materials are touted as potential candidates for NO₂ sensing at room temperature. However, most of the developed optoelectronic sensors to date are confined to the ultraviolet region with unsatisfactory performance. Herein, a room-temperature visible-light-activated optoelectronic NO₂ sensor based on 2D/2D T₃C₂T_x/WS₂ nanocomposites is presented. The T₃C₂T_x/WS₂-based gas sensor exhibited fast response/recovery rate, full reversibility, long stability, good selectivity, and low detection limit (10 ppb). In addition to the efficient interfacial charge separation provided by 2D/2D heterostructures, the improvement of optoelectronic NO₂ sensing performance was attributed to the visible-light-activation effects. This study provides a promising method to fabricate room-temperature high-performance gas sensors based on 2D nanomaterials.