Using DFT to explore the sensitivity of WSe2/phosphorene heterostructure toward HCN

Abstract

This study investigated the adsorption behavior of the HCN molecule on pristine and vacancy-defected (W and Se vacancies) and transition metal (TM; Sc, Ti, V, Cr, Mn, Fe, Co, Ni) -doped WSe2/phosphorene heterostructures through density-functional theory (DFT) calculations. As indicated by the results, the pristine and W-vacancy-defected WSe2/phosphorene structures exhibited weak adsorption capacity for HCN. Introducing Se vacancies enhanced the adsorption stability of HCN. Furthermore, combining TM impurities and Se vacancies decreased the adsorption distance, increased adsorption energy, and increased charge transfer, indicating a substantial improvement in the sensitivity of WSe2/phosphorene heterostructures to HCN. These findings suggest a potential new method for preparing gas sensors capable of detecting highly toxic hydrocyanic acid gas.