Enhanced SOx sensing performance of BC3 nanosheets functionalized with Na atoms: A first-principles study

Abstract Density functional theory calculations were performed to explore the interaction of gas molecules, including SO2 and SO3 with Na-functionalized C3B monolayers. Firstly, the electronic and geometric properties of Na-adsorbed C3B monolayers were examined to search for the most stable metal functionalized C3B based systems. The Na adatoms prefer the hollow site of the C-hexagon of C3B monolayer. Based on the charge density difference calculations, the electronic densities were depleted on the adsorbed Na metals. Thus, the adsorbed Na metals behave as charge donors. Contrary to the pure C3B monolayer with semiconducting property, the Na-adsorbed systems represent metallic character. The considered SO2 and SO3 gas molecules were adsorbed on the metal site of Na-functionalized C3B nanosheets through weak chemical bonds, which indicates the promising media for gas sensing and adsorption. The effects of van der Waals (vdW) interactions were taken into account for the adsorption of gas molecules on the considered C3B sheets. Thus, our results showed that Na-functionalized C3B sheet is a suitable material for gas sensing in the environment.