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Understanding the mechanism of hydrogen (H 2 ) formation from the conversion of water (H 2 O) and renewables on TiO 2 surfaces with cocatalysts via either photocatalysis or other catalytic processes is of significant importance to the successful design of efficient catalysts. Herein, we have investigated H 2 production from H 2 O, CH 3 OH, and C 2 H 5 OH on a Pt cluster covered rutile (R)-TiO 2 (110) surface (Pt clut /R-TiO 2 (110)) to address the mechanism of H 2 production. Experimental results demonstrate that surface adsorbates not only help H atom diffusion on Pt clut /R-TiO 2 (110) but also take part in H 2 production directly. Further density functional theory (DFT) calculations suggest that H 2 production on Pt clut /R-TiO 2 (110) occurs via a synergistic catalysis process between Pt clusters and interfacial adsorbates rather than a recombination reaction of H atoms on Pt clusters. This work provides new insight into H 2 production from H 2 O and renewables with Pt/TiO 2 catalysts, which may be applicable to H 2 production on other Pt cluster deposited metal oxide catalysts.

Ethyl acetate (EA) production from sequential ethanol (EtOH) photooxidation on a rutile(R)-TiO 2 (110) surface has been investigated by the temperature-programmed desorption (TPD) method at 355 and 266 nm. Significant EA product is detected under 266 nm irradiation, which is most likely to be formed via cross-coupling of primary dissociation products, aldehyde (CH 3 CHO) and ethoxy groups. On the contrary, EA formation at 355 nm is negligible. In addition, the initial rate of EA formation from EtOH at 266 nm is nearly 2 orders of magnitude faster than that at 355 nm. Quantitative analysis suggests that EA formation from sequential EtOH photooxidation on R-TiO 2 (110) is strongly dependent on photon energy or the energy of hot holes. This experimental result raises doubt about the traditional photocatalysis model on TiO 2 where charge carriers relax to their respective band edges prior to charge transfer to adsorbates during the photocatalytic process, leading to no dependence on photon energy in TiO 2 photocatalysis.