1T-ZrS<sub>2</sub> Monolayer Decorated with Sc, Ti, and V Single Atoms: A Potential Gas Scavenger for NO<sub>x</sub> and SO<sub>2</sub>.

Abstract

The intensification of industrialization and increasing energy consumption have led to elevated emissions of hazardous gases such as NO, NO₂, and SO₂, making their efficient capture and removal crucial for environmental remediation. In this work, first-principles calculations were employed to systematically investigate the adsorption behavior of these gases on single-atom-decorated (Sc, Ti, and V) 1T-ZrS₂ monolayers. The results indicate that the transition metal atoms preferentially occupy the hexagonal hollow sites of ZrS₂, forming an approximately octahedral coordination field and exhibiting characteristic <i>d</i>-orbital splitting. During gas adsorption, the decorated systems exhibit pronounced metal-to-adsorbate charge donation and strong <i>d</i>-<i>p</i> hybridization, indicative of strong chemisorption. Notably, Ti-ZrS₂ exhibits the strongest adsorption toward NO₂, inducing partial molecular dissociation and suggesting catalytic activity, whereas Sc- and V-decorated systems predominantly maintain molecular adsorption. Recovery time calculations indicate that the adsorption processes are comparatively stable, making these systems suitable for gas capture and pollution abatement. Overall, single-atom decoration provides an effective strategy to modulate the electronic structure and gas interactions of ZrS₂, highlighting its potential as an efficient gas scavenger for NO, NO₂, and SO₂.