Adsorption mechanism of graphene-like ZnO monolayer towards CO₂ molecules: Enhanced CO₂ capture

This work aims to efficiently capture CO₂ on two-dimensional (2D) nanostructures for effective cleaning of our atmosphere and purification of exhausts coming from fuel engines. Here, we have performed extensive first principles calculations based on density functional theory (DFT) to investigate the interaction of CO₂ on a recently synthesized ZnO monolayer (ZnO-ML) in its pure, defected and functionalized form. A series of rigorous calculations yielded the most preferential binding configurations of the CO₂ gas molecule on a ZnO-ML. It is observed that the substitution of one oxygen atom with boron, carbon and nitrogen on the ZnO monolayer resulted into enhanced CO₂ adsorption. Our calculations show an enriched adsorption of CO₂ on the ZnO-ML when substituting with foreign atoms like B, C and N. The improved adsorption energy of CO₂ on ZnO suggests the ZnO-ML could be a promising candidate for future CO₂ capture.