Electrophile–Nucleophile Paired Heteronuclear Dual-Site for Selective CO₂ Photoreduction to Ethanol via Oxygen-Tethered Asymmetric C–C Coupling

Photocatalytic CO₂ reduction to valuable multicarbon products like ethanol is a promising strategy for solar energy conversion, yet remains challenged by kinetically constrained C–C coupling and competitive C–O cleavage toward ethylene. Herein, an electrophile-nucleophile pairing strategy is developed by constructing atomically Cu–Zr heteronuclear dual sites within a porphyrinic framework, which can simultaneously reduce repulsion for C–C coupling and strengthen the C–O bond. The electron-deficient Zr, as a strong oxygen-affixed anchor, stabilizes critical *OCH intermediates via O-coordination, while adjacent electron-rich Cu sites drive *CO adsorption—inducing charge asymmetry between *OCH and *CO for kinetically favored dimerization. Subsequent hydrogenation selectively proceeds toward ethanol due to enhanced Zr–O stabilization that prevents C–O scission. The optimized catalyst achieved a near-unity ethanol selectivity at 87.8 µmol·g⁻¹·h⁻¹ using water as a scavenger under a CO₂ pressure of 0.5 MPa, which further increased to 195.1 µmol·g⁻¹·h⁻¹ at 1.5 MPa. This work establishes mismatched electrophile-nucleophile pairs as a versatile design principle for steering photocatalytic CO₂ reduction toward value-added multicarbon products.