Electronic and Optical Properties of Chloropicrin Adsorbed ZnS Nanotube: First Principle Analysis

Zinc sulfide nanotubes (ZnS NTs) have garnered significant attention as potential candidates for chemical sensing applications owing to their exceptional structural, electronic, and optical properties. In this study, we employed density functional theory (DFT) to explore the sensing capabilities of a ZnS (3,3) armchair single-walled nanotube (ZnS SWNT) for detecting chloropicrin (CP, CCl ₃ NO ₂ ), a highly toxic gas. To elucidate the sensing mechanism, we systematically analyze the adsorption configurations, charge transfer, band structure, density of states, optical absorption, and optical conductivity of the ZnS NT-CP system. Our findings reveal that the interaction between CP and ZnS NT induces notable changes in the nanotube's electronic and optical characteristics, including a substantial 40% reduction in the energy band gap for orientation A. Additionally, a good recovery time of 3.5 μs at room temperature, supported by the weak van der Waals-based physisorption phenomenon and significant red shift in the absorption spectra and optical conductivity peaks, highlight ZnS NT's potential for designing reusable CP sensors.