N2O ADSORPTION OVER FLAT AND DEFECTIVE Cu (110) SURFACES: PURE DFT AND DFT+U STUDIES INCLUDING vdW FORCES

Abstract

The adsorption of N2O on flat and defective Cu (110) surfaces has been studied using pure density functional theory (DFT) and DFT with Hubbard U, including van der Waals (vdW) corrections of the form vdW-DF. The calculations show that for GGA-PBE, as the exchange-correlation and vdW-DF functionals are considered, N2O molecule interacts very weakly with the flat Cu (110) surface, while the presence of the Cu-adatom results in better stability of adsorbed N2O compared to one on the perfect surface. Also, the inclusion of U parameter to PBE and vdW-DF functionals reduces the values of the adsorption energy relative to the standard PBE and vdW-DF functionals with or without spin-polarization. Finally, the analysis of the projected density of states shows a strong hybridization between the Cu-3d band and N-2p orbital. Our investigation suggests that the Cu (110) surface can serve as a catalytic medium that is able to adsorb the harmful N2O molecule.