Bifunctional Built-In Electric Field Across the Interface of Single Molecule and 2D Matrix Supramolecular Assembly for Highly Efficient and Selective Photocatalytic CO₂ Reduction

The sluggish interfacial charge transfer and constrained intrinsic catalytic activity in photocatalytic systems are major obstacles to the efficiency and selectivity of CO₂ photoreduction (CO₂PR). Herein, a novel organic–inorganic supramolecular assembly heterojunction (NiAl-ZnTCPP) comprising single molecules and 2D matrix is presented, featuring high-quality interfacial contact achieved through electrostatic interactions and hydrogen bonding. This comprehensive investigations unveil the formation of an effective interfacial built-in electric field (BEF) directed from NiAl-LDH toward ZnTCPP, which significantly boosts the activity and selectivity of CO₂PR. NiAl-ZnTCPP achieves an impressive CO yield of 1568.6 µmol g⁻¹ h⁻¹, exceeding the yields of ZnTCPP and NiAl-LDH by 25 and 5.6 times, respectively, while maintaining a remarkable 98% CO selectivity and extremely low hydrogen selectivity. Utilizing advanced experimental technologies, including diverse operando characterizations and theoretical simulations, the bifunctionality of the BEF is elucidated, which not only accelerates the transfer of photogenerated carriers from photosensitizer to NiAl-ZnTCPP, but also enhances the intrinsic activity of NiAl-ZnTCPP by modulating the electronic structure of nickel active sites (specifically lowering the energy barrier for ^*COOH to ^*CO conversion while improving charge transport capability). This work provides new insights into the application of molecule/2D matrix junctions to generate interfacial electric fields that enhance photocatalytic performance. © 2025 Wiley-VCH GmbH.