Coverage dependent CO2 activation on Ti2C(111) surface: Effect of intrinsic subsurface Carbon vacancies

Abstract

Using first principles density functional theory based calculations, we have studied the effect of subsurface C vacancies on the capture and activation of carbon dioxide (CO) on Ti-terminated TiC(111) surface. Additionally we also probed the effect of CO coverage on its adsorption. Our calculations show that, analogous to surface vacancies, sub-surface vacancies also enhances the strength of chemisorption. Further, coverage dependent adsorption studies showed that the lateral interactions between CO molecules are attractive in nature. Additionally, we find that dissociation of CO to CO and O have almost negligible dissociation barrier on this surface.