First-principles investigation of Pt-doped MoTe2 for detecting characteristic air decomposition components in air insulation switchgear

Abstract

Air-insulated switchgear plays a significant role in electrical engineering; the running stability of this equipment is required higher. In this work, the Pt-doped MoTe2 (Pt-MoTe2) monolayer is proposed as a novel sensing material for the detection of air decomposition components: NO2 and O3, to evaluate the operation status of air insulation switchgear. The Pt dopant is stably anchored on the MoTe2 surface with the binding force (Eb) of −3.02 eV, and the band gap decreases after Pt-doping on the pure MoTe2 monolayer. Besides, the Pt-MoTe2 monolayer behaves as chemisorption upon NO2 and O3 molecules adsorption with adsorption energy (Ead) of −1.750 eV, −2.045 eV, respectively. Furthermore, the NO2 and O3 molecules behave as electron-acceptor withdrawing charges from the Pt-MoTe2 monolayer, based on the Hirshfeld analysis. Comparing two gas systems, it is found that band gap decreases in both gas systems, and the degree of decrease varies significantly, which makes it possible to develop resistance-type gas sensor to detect NO2 and O3 molecules. Our calculations give an insight into the physicochemical property of Pt-MoTe2 monolayer, and elucidate their promising potential as novel gas sensors for air insulating switchgear.