Modulation of Pt species on oxygen vacancies enriched TiO2 via UV illumination for photocatalytic performance optimization<bold> </bold>

Due to expense and rarity of Pt element, optimization of Pt would be of importance for developing highly active Pt/TiO2 catalysts with low Pt loading dosage. In this study, the Pt nanoparticles, located on the surface of oxygen vacancies enriched TiO2 (V-TiO2), are redispersed through a facile pretreatment under UV illumination with the contribution of surface oxygen vacancies. Such process subsequently leads to the optimization of surface active species (Pt-0, PtOads, and O-ads(-)) on Pt/V-TiO2, which promotes the photocatalytic performance of CO oxidation. With an appropriate Pt dispersion and an optimized proportion of active Pt species, Pt/V-TiO2 after 2.0 h UV illumination pretreatment (Pt/V-TiO2-2) shows the best photocatalytic performance. Pt/V-TiO2-2 displays ca. 21-fold photocurrent response and 1.7-fold boosted photoactivity compared to Pt/V-TiO2, respectively.<bold> </bold>