Photoacid Generator Significantly Enhanced Photocatalytic Reforming of Methanol into Hydrogen Over Titania

Hydrogen (H2) has been considered as a potential alternative energy candidate because it has high energy storage capacity and no hazardous by-products are produced upon its combustion; the production of H2 via the photocatalytic alcohol reforming has motivated a broad research interest. Here, we develop TiO2 photocatalyst coupled with photoacid generator (PAG) for significantly augmented photocatalytic H2 generation by catalytic reforming of neat methanol. The H2 evolution rate over TiO2-PAG is 1412.4 µmol g-1 h-1, which is 3.5 times higher than bare TiO2 (397.4 µmol g-1 h-1). The optimal sample exhibits an apparent quantum yield (AQY) of 5.68% at λ = 365 nm. The enhancement of the photocatalytic performance is due to abundant H+ ions generated from α-hydrogen abstraction by PAG, which can be effectively combined with photoinduced electrons from TiO2 and reduced to H2. In addition, strong metal-support interaction (SMSI) between Pt and TiO2 removes adsorbed H2 from the surface of Pt─TiO2, keeping the surface fresh and maintaining high efficiency and excellent recycling stability of obtained photocatalysts. The combination of the two emerging functional materials represents a simple but economical and powerful approach for highly efficient methanol photocatalytic reforming into hydrogen.