Surface and Defect Engineering Coupling of Charge Shuttle and Redox Site in Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub>/g-C<sub>3</sub>N<sub>4</sub> for Efficient Photocatalytic C(sp<sup>3</sup>)–H Bond Activation
Chunhua Wang, Yang Ding, Zhirun Xie, Yannan Wang, Yang Li, Ning Han, Q. N. Xu, Yuekun Lai, Michael K.H. Leung, Biao Liu, Bao‐Lian Su, Yun Hau Ng
Abstract
Solar-driven organic synthesis using halide perovskites (HPs) has garnered much attention, but their unsatisfactory conversion efficiency limits further applications. Addressing charge dynamics and redox site issues is a straightforward approach to improving performance. Herein, we report the synergistic charge separation and active site modulation in lead-free Cs 3 Bi 2 Br 9 HP using N-vacancy reticular g-C 3 N 4 nanosheet for selective C(sp 3 )–H bond activation. This regulation exhibits a strong interfacial interaction, enabling effective charge transfer with more active sites. Theoretical calculations and experimental characterizations detailed enhanced charge separation and reduced energy barriers for surface photoredox reactions. When applied to toluene oxidation under simulated solar light, the optimized photocatalyst achieves a total conversion rate of 6865.3 μmol g –1 h –1 and an outstanding benzaldehyde selectivity of over 92%, outperforming most reported HP-based photocatalysts. This work offers a universal strategy for developing efficient HP photocatalysts for solar-to-chemical energy conversion.