TiO2–Doped GeSe Monolayer: A highly selective gas sensor for SF6 decomposed species detection based on DFT method.

[Display omitted] • Firstly, TiO 2 -Doped GeSe Monolayer are studied. • The introduction of dopants improves the selectivity and sensitivity of GeSe. • Doped GeSe have suitable sensing traits to perfect adsorption and desorption. • The change of conductivity is critical to production of resistive gas sensors. The detection of SF 6 decomposition species has been a crucial method of fault diagnosis for insulation equipment. Faced with problems of poor selectivity, low sensitivity and non-recyclability of existing nano-gas sensors, TiO 2 -doped GeSe monolayer is proposed. The doping of TiO 2 nanoparticle greatly improves the conductivity of GeSe monolayer and the selective for SF 6 decomposition species, SO 2 > H 2 S > SOF 2 > SO 2 F 2. Moreover, electron transfer of SF 6 is further inhibited. When gases are adsorbed, the reduction of the difficulty of electron transition ensures the high sensitivity detection in practical application, especially SO 2. Ideal adsorption energies ensure that TiO 2 -GeSe monolayer has excellent response and recovery ability, which theoretically solves the industrial problem of recycling. In addition, compared with pure GeSe and other normal 2D materials, TiO 2 -GeSe exhibits excellent sensing detection advantages. This study provides a theoretical foundation for resistive chemical sensors used in industrial insulation equipment. [ABSTRACT FROM AUTHOR]