Sensing Application of Ni-Doped WS\(_2\) on Industrial Pollutants - A DFT Approach

Abstract

Density functional theory (DFT) has been used to thoroughly examine the structures, electronic and adsorption characteristics of Ni-doped WS₂ (Ni_XWS_2-X (X=1, 2, 3)), as well as the adsorption characteristics of various gas molecules (NO, NO₂, NH₃, BCl₃ and SO₂). The physical and chemical interactions before and after gas adsorption can be assessed by determining the adsorption distance, adsorption energy, and charge transfer. The electron transport characteristics are studied by I-V characteristics and the transmission spectrum (T-S) analysis. The findings show that higher concentration Ni-doped WS₂ (Ni₃W₁₆S₂₉) has better conductivity and enormous charge transfer when compared with other concentrations of Ni-doped WS₂. Further Ni₃W₁₆S₂₉ is utilized for the adsorption study on the toxic gases. Additionally, the Ni₃W₁₆S₂₉ exhibits stronger adsorption for the NO₂ and BCl₃ gases. Subsequently, there is electron localization overlap for certain gas molecules, which highlights the physisorption as well as the chemisorption character of gas molecules. The I-V and T-S analysis of Ni₃W₁₆S₂₉ shows more change in the conductivity after the adsorption of BCl₃ gas molecules. The theoretical results suggest that Ni₃W₁₆S₂₉ systems have the potential to be a BCl₃ gas sensor. These scientific discoveries provide a concept for practical use and experimental validation for dangerous gas detection by utilizing doped 2D material.