Investigation of the active sites of CO2 hydrogenation to methanol over a Cu-based catalyst by the UBI-QEP approach

Activation energies of elementary reactions in the methanol synthesis from CO2/H-2 over clean and oxygen-modified Cu (100) surfaces have been calculated using the Unity Bond Index-Quadratic Exponental Potential approach. By comparison of the energies at different coverages of oxygen, it was found that there is a volcano-shaped relation between the coverage of oxygen on the Cu (100) surface and the reaction activity, suggesting that a ratio of Cu+/Cu-o species on the surface controls the catalytic activity. (C) 2000 Elsevier Science B.V. All rights reserved.