Pd-Decorated WTe₂ Monolayer as a Favorable Sensing Material toward SF₆ Decomposed Species: A DFT Study

Based on density functional theory, this work first investigates the Pd-decorating property on the pristine WTe2 monolayer and then simulates the adsorption performance of a Pd-decorated WTe2 (Pd–WTe2) monolayer on SO2 and SOF2 molecules, in order to explore its sensing potential for SF6 decomposed species. It is found that the Pd atom can be stably anchored on the top of the W atom of the WTe2 monolayer with a binding energy of −2.43 eV. The Pd–WTe2 monolayer performs chemisorption on SO2 and SOF2, with adsorption energies of −1.36 and −1.17 eV, respectively. The analyses of the band structure and density of states reveal the deformed electronic property of the WTe2 monolayer by Pd-decoration, as well as that of the Pd–WTe2 monolayer by gas adsorption. The bandgap of the Pd–Wte2 monolayer is increased by 1.6% in the SO2 system and is decreased by −3.9% in the SOF2 system, accounting for the sensing response of 42.0 and −56.7% for the detection of two gases. Moreover, the changed work function (WF) in two gas systems in comparison with that of the pristine Pd–WTe2 monolayer suggests its potential as a WF-based gas sensor for sensing two gases as well. This paper uncovers the gas sensing potential of the Pd–WTe2 monolayer to evaluate the operation status of SF6 insulation devices, which also illustrates the strong potential of WTe2-based materials for gas sensing applications in some other fields.

Перевод пока недоступен