Pt single atoms as electron shuttle for high-quantum-efficient photocatalytic methanol dehydrogenation

Photocatalytic methanol dehydrogenation affords HCHO and H 2 , capable of replacing the current methanol oxidation technologies for HCHO production. However, the charge transfer from bulk of photocatalyst to methanol and intermediates has barrier, leading to quantum efficiency far from 100 %. Herein, we synthesized TiO 2 -supported Pt single atoms (Pt 1 /TiO 2 ) that works as an electron shuttle to promote electron extraction from the bulk of TiO 2 and transfer it to protons. The Pt 1 supported on TiO 2 reduces the migration energy of electrons from 0.57 to 0.23 eV, thus fostering electron extraction from bulk of TiO 2 to surface. Electrons trapped on Pt 1 active sites can be transferred to protons for H 2 evolution. Therefore, the Pt 1 /TiO 2 produces H 2 and HCHO from methanol with formation rates of 102.8 and 80.4 mmol g catal. −1  h −1 , respectively, which are 1.7 folds of Pt/TiO 2 prepared by an impregnation method. The quantum efficiency of methanol dehydrogenation is 52 % at ambient temperature and increased to 84 % at 75 °C. This study offers fundamental insights into charge extraction and transfer mechanisms for dehydrogenation reactions.