Enhancement of catalytic activity of Ir/TiO2 by partially reduced titanium oxide in aerobic oxidation of alcohols

► The catalytic activity of 2 wt% Ir/TiO2 in alcohol oxidation with molecular oxygen was enhanced by high-temperature hydrogen reduction. ► Kinetic analysis revealed that adsorption of alcohol was enhanced by high-temperature hydrogen reduction. ► Formation of partially reduced titanium oxide by high-temperature hydrogen reduction is well known phenomenon as the SMSI effect. ► Coordinatively unsaturated titanium sites formed by the SMSI effect may work as coordination sites of alcohols to enhance catalytic activity.