2D/2D heterojunction of g–C <sub>3</sub> N <sub>4</sub> /SnS <sub>2</sub> : room-temperature sensing material for ultrasensitive and rapid-recoverable NO <sub>2</sub> detection
Quan Sun, Juanyuan Hao, Shengliang Zheng, Peng Wan, Jialu Li, Di Zhang, Yanqiu Li, Tingting Wang, You Wang
Abstract
Abstract Heterojunction engineering plays an indispensable role in improving gas-sensing performance. However, rational heterojunction engineering to achieve room-temperature NO 2 sensing with both high response and rapid recovery is still a challenge. Herein, a 2D/2D heterojunction of g–C 3 N 4 /SnS 2 is designed to improve the sensing performance of SnS 2 and used for ultrasensitive and rapid-recoverable NO 2 detection at room temperature. The pristine SnS 2 fails to work at room temperature because of its high resistivity and weak adsorption to NO 2 . After combination with g–C 3 N 4 nanosheets, the g–C 3 N 4 /SnS 2 -based sensor exhibits an extremely high response (503%) and short recovery time (166 s) towards 1 ppm NO 2 at room temperature. The improved sensing performance is primarily attributed to the increased adsorption sites and enhanced charge transfer induced by the 2D/2D heterojunctions with large interface contact area. This achievement of g–C 3 N 4 /SnS 2 2D/2D heterostructures demonstrates a promising pathway for the design of sensitive gas-sensing material based on a 2D/2D heterojunction strategy.