Pristine and Ag decorated In2O3 (110): A gas-sensitive material to selective detect NO2 based on DFT study

Abstract

High-performance sensors for toxic gases have been the goal of research in the industry. In this paper, the adsorption of seven toxic target gases, NO, NO2, NH3, H2S, CO, CH4 and HCHO, on the intrinsic and modified In2O3 (110) surface is investigated based on Density functional theory (DFT). Relevant parameters such as adsorption energy, charge transfer, adsorption distance and band gap are calculated and a combination of density of states (DOS), deformation charge density (DCD) and frontier molecular orbital theory are employed to investigate the application of In2O3 (110) in gas sensing. Theoretical recovery times were also calculated to provide a basis for the reusability of In2O3 (110) gas sensors. Our calculations show that the intrinsic In2O3 (110) surface responds to several toxic gases, while the Ag dopant enhances the adsorption of In2O3 on NO2 while suppressing its response to HCHO and H2S gases, making Ag-doped In2O3 (110) a promising candidate for a highly selective sensor for NO2.