Carbon disulfide (CS2) adsorption and dissociation on the Cu(100) surface: A quantum chemical study

Abstract

Density functional theory (DFT) is used to examine the adsorption and dissociation of CS2 on the Cu(100) surface. This study evaluates the adsorption energies and geometries of the species (CS2, CS, C and S) adsorption on the Cu(100) surface, as well as that coadsorption of CS and a S atom, and that coadsorption of C atom and two S atoms. The results indicate that the species (CS2, CS, C and S) are strongly chemadsorbed on the Cu(100) surface through the CCu and/or SCu bond with an increased adsorption energy (C/S/S>S/CS>CS2). Two pathways for CS2 dissociation on the Cu(100) surface are constructed, and the energy barrier and reaction energy of each step are calculated. It shows that the dissociated energy barrier of the second CS bond is 0.25eV higher than that of the first CS bond in the pathway 1, but in the pathway 2, the dissociated energy barrier of the second CS bond is 0.11eV lower than that of the first CS bond. Comparing the highest dissociated energy barrier of pathway 1 (0.68eV) and pathway 2 (0.5eV), the structure of S/C/S(II) is regarded as a preferable product for the dissociation of CS2 on the Cu(100) surface.