Interfacial molecular regulation of TiO₂ for enhanced and stable cocatalyst-free photocatalytic hydrogen production

On the basis of the inherent property limitations of commercial P25-TiO₂, many surface interface modification methods have attracted substantial attention for further improving the photocatalytic properties. However, current strategies for designing and modifying efficient photocatalysts (which exhibit complicated manufacturing processes and harsh conditions) are not efficient for production that is low cost, is nontoxic, and exhibits good stability; and therefore restrict practical applications. Herein, a facile and reliable method is reported for in situ amine-containing silane coupling agent functionalization of commercial P25-TiO₂ by covalent surface modification for constructing a highly efficient photocatalyst. As a consequence, a high efficiency of H₂ evolution was achieved for TiO₂-SDA with 0.95 mmol h^-1 g^-1 (AQE ∼45.6 % at 365 nm) under solar light irradiation without a co-catalyst. The amination modification broadens the light absorption range of the photocatalyst, inhibits the binding of photogenerated carriers, and improves the photocatalytic efficiency; which was verified by photochemical properties and DFT theoretical calculations. This covalent modification method ensures the stability of the photocatalytic reaction. This work provides an approach for molecularly modified photocatalysts to improve photocatalytic performance by covalently modifying small molecules containing amine groups on the photocatalyst surface.