Interfacial Bi–O Bridge Elevated Bi <i>p</i>-Band Center Boosting Photocatalytic C(<i>sp</i>³)–H Bonds Oxidation

Photocatalytic selective oxidation of C(sp3)–H bonds in hydrocarbons into value-added aldehydes is a promising yet challenging approach due to the higher reactivity of products than reactants. Regulating reactive oxygen species has been proved a feasible way to prevent further oxidation of aldehydes. Herein, uniform Cs3Bi1.8Sb0.2Br9 (CSBB) nanodots anchored on ultrathin triazine zirconium carboxylate metal–organic layers (ZrTATB) were fabricated through interfacial Bi–O bonds. This not only enhanced the separation of charge carriers but also elevated the Bi p-band center to the Fermi level by generating electron-deficient Biδ+ sites, which, in turn, reduced the antibonding orbital occupancy of Bi–Oads in the CSBB-ZrTATB composite. Consequently, 1O2 as the dominant reactive oxygen species was generated through energy transfer of photoexcited excitons to O2, whereas •O2– over pristine CSBB is more feasible. Notably, the optimized CSBB-75-ZrTATB exhibited an impressive toluene conversion rate of 16,495 μmol g–1 h–1 under solvent-free conditions, with benzaldehyde selectivity maintained as high as 88% over extended light exposure. Moreover, high electrical energy-to-benzyl alcohol and benzaldehyde (ETB) conversion efficiency reached 0.0603%. This work provides insights into the rational construction of chemical bonds to regulate the electronic structure of metal halide perovskites and demonstrates their potential application in photocatalytic aerobic oxidation.