Sulfur-driven in situ oxygen vacancy engineering in TiO2 enables efficient photocatalytic transfer hydrogenation of furfural

Sulfur incorporation facilitates in situ oxygen-vacancy formation in TiO 2 . • S–O formation and S–V O coupling regulate the electronic structure of TiO 2 . • Oxygen vacancies promote furfural adsorption and activation. • Sulfur-mediated defect engineering enables selective furfural hydrogenation. • S 0.75 -TiO 2 achieves 44.0 mmol FA ·g cat. −1 ·h −1 with 99.5% FA selectivity. Photocatalytic transfer hydrogenation (PTH) of biomass-derived furfural (FF) to furfuryl alcohol (FA) using methanol as a green hydrogen donor represents a sustainable route for producing value-added chemicals, yet developing robust noble-metal-free catalysts remains challenging. Herein, we present a sulfur-doped TiO 2 photocatalyst exhibiting exceptional activity and selectivity for FF hydrogenation. The optimized catalyst delivers an impressive space-time FA yield of 44.0 mmol FA ·g cat. −1 ·h −1 with 99.5% selectivity under 500 mW·cm −2 irradiation, surpassing most state-of-the-art systems. Comprehensive characterizations and theoretical calculations reveal that lattice-substituted sulfur atoms form surface S–O species, driving oxygen vacancy formation and modulating the electronic structure of TiO 2 . The synergistic interaction between S species and V O sites regulates the electron density at active sites, thereby markedly promoting FF adsorption/activation, charge separation, and targeted hydrogenation. This work establishes a strategy for constructing high-efficiency, non-precious photocatalysts through sulfur-mediated oxygen-vacancy engineering. Download: Download high-res image (135KB) Download: Download full-size image