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

• Published in: Applied surface science Vol. 634; p. 157652
• Main Authors: Wang, Li, Zhou, Qingxiao, Hou, Jie, Liu, Xiaoyang, Ju, Weiwei, Zhao, Zenghui, Wang, Yajing
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.10.2023
• Subjects: Adsorption; DFT; HCN; WSe2/phosphorene heterostructure; WSe2/phosphorene heterostructure; HCN; DFT; Adsorption
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2023.157652

Density functional theory is used to study the adsorption of HCN molecule on perfect, vacancy-defected (W- and Se-vacancy), and transition metal (TM; Sc, Ti, V, Cr, Mn, Fe, Co, Ni) -doped WSe2/phosphorene heterostructures. The results indicate that the introduction of Se-vacancy enhances the adsorption stability of HCN molecule. Furthermore, the combination of TM-impurity and Se-vacancy significantly improves the sensitivity of WSe2/phosphorene heterostructure to HCN. [Display omitted] •The adsorption of HCN on perfect, and W-vacancy defected WSe2/phosphorene heterostructure is physical adsorption.•The introduction of Se-vacancy enhanced the adsorption stability of HCN molecule.•Adsorption of HCN on the TM-doped WSe2/phosphorene with Se-vacancy defect is chemisorption.•The Se-vacancy defected WSe2/phosphorene doped with V, Fe and Co can be used to detect the presence of HCN. 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.