The curious case of CO2 dissociation on Cu(110)

Dissociation of CO2 on copper surfaces is an important model system for understanding the elementary steps in catalytic conversion of CO2 to methanol. Using molecular beam-surface scattering methods, we measure the initial dissociation probabilities (S-0) of CO2 on a flat, clean Cu(110) surface under ultrahigh vacuum conditions. The observed S-0 ranges from 3.9 x 10(-4) to 1.8 x 10(-2) at incidence energies of 0.64-1.59 eV. By extrapolating the trend observed in the incidence energy dependence of S-0, we estimate the lower limit of the dissociation barrier on terrace sites to be around 2 eV. We discuss these results in the context of what is known from previous studies on this system using different experiments and theoretical/computational methods. These findings are anticipated to be valuable for correctly understanding the elementary steps in CO2 dissociation on Cu surfaces.