Oxygen vacancy regulated valence states of Pt on rutile TiO2 promote catalytic oxidation of HCHO

Anatase-TiO2-supported Pt (Pt/TiO2(A)) is a well-known supported catalyst for catalyzing the oxidation of formaldehyde (HCHO). However, rutile TiO2 (TiO2(R)) has not been widely utilized for this reaction due to its inferior performance. In this study, we have developed a novel approach involving NaBH4-induced oxygen vacancy manipulation to regulate the valence states of Pt on TiO2(R). By employing a large excess of NaBH4 (nNaBH4/nPt = 2000), we were able to generate an extraordinary concentration of oxygen defects and electron-rich sites on the surface of TiO2(R), resulting in the concentration of Pt0 on Pt/TiO2(R)− 2000 exceeding that on Pt/TiO2(A)− 2000. The newly synthesized Pt/TiO2(R)− 2000 catalyst exhibited a remarkably high turnover frequency (TOF) of 160.2 h−1, which is approximately five times that of Pt/TiO2(R)− 20. The discrepancy in the reaction mechanisms between rutile and anatase was identified as the critical factor underlying the vastly different performances observed.