High Catalytic Activity of Pt/Al₂O₃ Catalyst in CO Oxidation at Room Temperature—A New Insight into Strong Metal–Support Interactions

The concept of very strong metal–support interactions (VSMSI) was defined in regard to the interactions that influence the catalytic properties of catalysts due to the creation of a new phase as a result of a solid-state chemical reaction between the metal and support. In this context, the high catalytic activity of the 1%Pt/Al2O3 catalyst in the CO oxidation reaction at room temperature was explained. The catalyst samples were reduced at different temperatures ranging from 500 °C to 800 °C and characterized using TPR, O2/H2 titration, CO chemisorption, TPD-CO, FTIR-CO, XRD, and TOF-SIMS methods. Based on the obtained results, it was claimed that with very high temperature reduction (800 °C), nonstoichiometric platinum species [Pt(Cl)Ox] strongly anchored to Al2O3 surface are formed. These species act as the oxygen adsorption sites.