First principles study on the adsorption of Pt_n (n = 1–4) on γ-Al₂O₃(1 1 0) surface

Highlights: • The growth ability of the supported Pt_n cluster is weaker than the gas phase Pt_n clusters. • Basin structures on both of the clean and hydrated γ-Al₂O₃ (1 1 0) surfaces help to stabilize the Pt clusters. • The hydrogen located at the tri-coordinated surface O atoms was the most effective hydrogen supplier. • The Pt_n (n = 3–4) are much more active than Pt_n (n = 1–2) for hydrogen desorption. - Abstract: The density functional theory (DFT) was applied to investigate the adsorption and growth of Pt_n (n = 1–4) clusters and hydrogen spillover on γ-Al₂O₃ surface, which is of importance for many catalysis reactions. It was found that the growth ability of the supported Pt_n cluster is weaker than the gas phase Pt_n clusters. Basin structures on both of the clean and hydrated surfaces were found to stabilize the Pt clusters. For the hydrated surface, the basin structure, together with the size of Pt_n cluster, was also found to take trivial impacts on the hydrogen spillover. The most feasible supplier of H species on the hydrated γ-Al₂O₃ surface was identified. Additionally, it was interesting to found that there would be an optimized size of the supported Pt_n cluster at n > 3