Activation of carbon dioxide on zinc oxide surfaces doped with cerium

Abstract

AbstractThe adsorption of carbon dioxide on the surfaces of zinc oxide doped with cerium was studied. For this, a theoretical study was carried out using computational simulations based on density functional theory to determine possible improvements in photocatalytic activity. for the capture and dissociation of carbon dioxide. Calculations were performed using density functional theory within the Perdew-Burke-Ernzerhof generalized gradient approximation, also the Hubbard correction together with ultrasmooth atomic pseudopotentials and a basic plane wave implemented in the Quantum-ESPRESSO package. The doping concentration level considered in this work was 6.25%, among the results, the semiconducting character of zinc oxide was evident from the density of states calculations, it was also found that by adding cerium impurities to zinc oxide, the values of the lengths and angles of the bonds vary a little, this may be due to the small difference in covalent radius that the zinc atom has with respect to the cerium atom, consequently, changes occurred in the electronic properties that consist in intermediate states in the energy bandgap located around the Fermi energy. This may suggest that the cerium-doped zinc oxide system can probably absorb visible light, which could lead to possible improvements in the photocatalytic properties of the material. Furthermore, we found that by adding carbon dioxide to the cerium-doped zinc oxide surface, the carbon dioxide is activated and this could suggest the dissociation or reduction of this contaminant.