Transition metal (Ti, Cu, Zn, Pt) single-atom modified graphene/AS2 (A = Mo, W) van der Waals heterostructures for removing airborne pollutants

Abstract

Air pollution is a worldwide issue that affects human health and the environment. The scientific community tries to control it through different approaches, from experimental to theoretical assessments. Here, we perform DFT calculations to describe CO₂, NO₂, and SO₂ detection on a single-atom (Ti, Cu, Zn, Pt) graphene supported on 2D molybdenum disulfide (MoS₂) and tungsten disulfide (WS₂). Transition metal single atoms on graphene improve the monolayer reactivity by generating an effective way to remove airborne pollutants. Results indicate that SO₂ and NO₂ chemically adsorb on all tested transition metals, whereas CO₂ stands on top of the incorporated atoms through van der Waals interactions. Since strong Ti–O interactions appear, the Ti single-atom graphene/MoS₂(WS₂) systems efficiently remove CO₂ from the environment. Compared to pristine graphene, our proposed heterostructures improve the SO₂, NO₂, and CO₂ adsorption energies. The heterostructures' electronic properties change once the molecules interact with the transition metals, generating sensible and selective pollutant molecule detection and removal.