Red-Light-Catalytic Selective Oxidation of Benzyl Alcohol Mediated by Oxygen Vacancy Abundant Ti-Doped MnCo2O4

Selective transformation of biomass platform compounds through photocatalytic is regarded as a green and sustainable process. In this study, spinel bimetallic oxide was used as an efficient red light photocatalyst for organic conversion. Ti-doped MnCo₂O₄ spinel nanomaterials with bimetallic sites were synthesized via a one-pot method, demonstrating excellent performance in the red-light-driven selective aerobic oxidation of benzyl alcohol to benzaldehyde. Under mild conditions, the reaction achieved 90.1% conversion and 99.9% selectivity. Ti doping facilitated the formation of oxygen vacancies, while the mesoporous structure of MnCo₂O₄ enhanced charge separation and migration, resulting in a narrower band gap (1.44 eV). DFT calculations revealed that oxygen vacancies modify the energy band structure, promote carrier excitation, and reduce the bandgap. Additionally, the high specific surface area provided abundant photocatalytic active sites. XPS, EPR and photoelectrochemical measurements confirmed the excellent red-light responsiveness and efficient separation of photogenerated electron-hole pairs in the Ti-doped MnCo₂O₄ photocatalyst. The synergistic effect of Ti doping and the hierarchical mesoporous structure significantly enhanced the photocatalytic performance. This work provides a promising strategy for producing high value-added chemicals through efficient photocatalysis.