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.