Photochemical modulated metal-support-interaction of Pt-rutile TiO2 and the effects on catalytic oxidation of HCHO

The metal-support-interaction (MSI) has been attracting close attention for HCHO oxidation due to its specific electronic and structural effects. Here, we report a mild photochemical strategy for the modulation of the MSI between Pt and rutile TiO2. By increasing the irradiation intensity, more electrons were enriched on Pt and the contact between Pt and TiO2 became stronger, and even induce the encapsulation of Pt nanoparticles by TiO2. The apparent activation energies were 45.4 and 38.8 kJ/mol over the samples with weaker (P40) or stronger (P500) MSI, while decreased to 9.1 kJ/mol on the sample (P120) with moderate MSI. The promoted activity was much higher than that of most reported anatase and P25-based Pt/ TiO2 catalysts. The balanced electronic structure and spatial structure favor the activation of oxygen species, thus promoting both the conversion of dioxymethylene to HCOO- species and the following decomposition of HCOO-.