Map of 20 reactions that take place during vapor–solid phase photocatalytic dehydrogenation of ethanol on metal‐loaded TiO2.

We report the map of 20 reactions that take place during vapor‐phase photochemical dehydrogenation of ethanol on four metal‐doped TiO2 (Mn/TiO2, Mn = nanoparticles of Pd, Pt, Au, and Cu) under solar simulated light. The reactions are sensitively affected by the moisture amount and the nature of the carrier gas. To construct the above map, we also used CH3CHO, CH3CO2H, (C2H5O)2CHCH3, and CH3CO2C2H5, respectively, as an independent starting reagent. Amazingly, Mn/TiO2 not only serves as photocatalysts but also as thermocatalysts for various reactions that appear in the above map. The reaction is proposed to proceed by a radical mechanism in which photoinduced electron transfer from the valence band to the conduction band of TiO2 is the initial step and the subsequent electron injection from organic reactants to the hole in the TiO2 valence band. This report also features highly valuable unprecedented reactions, which bear great potential to be commercialized. [ABSTRACT FROM AUTHOR]