Enhanced Solar Hydrogen Evolution over In Situ Gold-Platinum Bimetallic Nanoparticle-Loaded Ti3+ Self-Doped Titania Photocatalysts

This work presents a photochemical and thermal treatment strategy to prepare in situ gold-platinum bimetallic nanoparticle-loaded titania photocatalysts with self-doped Ti3+ states (Au-Pt/Ti3+ nc-TiO2). In situ loading of Au-Pt bimetallic nanoparticles and Ti3+ self-doping in the TiO2 crystal lattice result in excellent solar light photocatalytic activity. The Au-Pt/Ti3+ nc-TiO2 displays an improved hydrogen evolution rate (98.53 mmol h(-1) g(-1)) when compared to in situ gold-loaded and in situ platinum-loaded titania (Au/Ti3+ nc-TiO2 and Pt/Ti3+ nc-TiO2, respectively) photocatalysts. The Au-Pt/Ti3+ nc-TiO2 photocatalyst is further restructured into titania inverse opal (Au-Pt/Ti3+ io-TiO2) photocatalyst by a facile colloidal photonic crystal (CPC) infiltration method. The Au-Pt/Ti3+ io-TiO2 photocatalyst displays a superior solar hydrogen evolution profile (181.77 mmol h(-1) g(-1)) compared to all the other photocatalysts investigated for hydrogen production experiments, which makes them potential candidates for solar water splitting.