Ce–Ag Active Bimetallic Pairs in Two-Dimensional SnS<sub>2</sub> for Enhancing NO<sub>2</sub> Sensing
Huimin Yang, Zhenming Du, Yazhou Yang, Qirui Wu, Chaofan Ma, Huiyu Su, Xiaoxia Wang, Dawen Zeng
Abstract
Developing gas sensors capable of efficiently detecting harmful gases is urgent to protect the human environment. Here, an active Ce–Ag bimetallic pair was innovatively introduced into SnS 2, which successfully exhibited excellent NO 2 gas sensing performance. 0.8% Ce–SnS 2 –Ag showed a gas sensing response of 5.18 to 1 ppm of NO 2 at a low temperature of 80 °C, with a lower limit of detection as low as 100 ppb. DFT calculations revealed that Ce atoms are substituted into the main lattice of SnS 2, which opens up the interlayer spacing and serves as an anchor point to fix the Ag atoms in the interlayer. The Ce–Ag bimetallic pairs successfully modulate the electronic structure of SnS 2, which promotes the adsorption and charge transfer between NO 2 and Ce–SnS 2 –Ag and thus achieves such an outstanding gas sensing performance. This work opens an avenue for the rational functional modification of SnS 2 with an optimized electronic structure and enhanced gas sensing.