Defect-mediated reactivity of Pt/TiO2catalysts: the different role of titanium and oxygen vacancies

Defects are ubiquitous in oxide supports and can often tune the catalytic property of supported metal catalysts. This work describes the distinct role of titanium and oxygen vacancies of TiO(2)supports in the catalytic performance of supported Pt catalysts for CO oxidation. Pt was loaded on the TiO(2)supports with oxygen vacancies (V-O-TiO2) and titanium vacancies (V-Ti-TiO2). It was found that different defects of TiO(2)could distinctively modify the electron property of Pt and thereby CO adsorption strength. The strength of CO adsorption on Pt/V-Ti-TiO(2)is enhanced, while that of Pt/V-O-TiO(2)becomes weaker. Additionally, the presence of defects would also promote the reducibility of catalysts. On the account of the superior redox ability, both Pt/V-Ti-TiO(2)and Pt/V-O-TiO(2)exhibit a higher activity than Pt supported on normal TiO(2)for CO oxidation.