Strongly Modified Scaling of CO Hydrogenation in Metal Supported TiO Nanostripes

The boundary between a metal-oxide and its metal support (metal-oxide|support) provides an intriguing structural interface for heterogeneous catalysis. The hydrogenation of CO is a reaction step believed to be rate limiting in electrochemical CO₂ reduction. Density functional theory (DFT) calculations were performed to study this reaction step for a class of catalytic material: metal supported TiO nanostripes. The most stable adsorption sites were identified for all metal supports which showed a striking difference in adsorbate geometry between the strong and weak binding metal supports. The modified CO hydrogenation scaling shows a significant strengthening over (111) and (211) transition metal surfaces. Such enhancement can be attributed to a combination of geometrical effects and metal-oxide|support electronic interactions. A correlation analysis was performed to identify the key features needed to accurately predict∗CO and∗CHO adsorption energies on the TiO nanostripes and to further validate our physical analysis of the results. This structural motif seems to be a promising avenue to explore scaling modification in other metal-oxide materials and reactions.