Sinusoidal Nanocurvature Interface of Mesoporous Nanoreactors Enhances Electron Migration Pathway for Photocatalytic C–C Coupling

The kinetic mismatch between the proton-coupled electron transfer pathway and the energy barrier of the C–C coupling severely restricts the selective photocatalytic CO2 reduction to high-value C2 products. Concave–convex curvature interface engineering offers a potent strategy to optimize asymmetric bimetallic sites and boost catalytic activity yet remains largely unexplored. Herein, we report a Ga atom-doped CuO photocatalyst with a sinusoidal nanocurvature interface, synthesized via a shear force-driven interface micellar coassembly strategy. 3D reconstruction of individual mesoporous nanoparticles presents a spindle-like structure and demonstrates a continuous “concave–convex–concave” sinusoidal nanocurvature interface. Bader charge analysis reveals that the sinusoidal interface induces the formation of an electron migration pathway, which reduces the electron migration resistance while increasing the number of transferred electrons. Experimental results and theoretical analyses demonstrate that the introduction of Ga atoms, which form asymmetric Ga–O–Cu sites, not only further reinforces the proton-coupled electron transfer pathway but also optimizes the local Cu coordination environment, stabilizes the key *CO and *CHO intermediates, and significantly lowers the energy barrier of the rate-determining step. The optimized catalyst achieves a C2H4 yield of 13.63 μmol g–1 h–1 with an electron-basis selectivity of up to 85.5%. This work opens a new horizon for engineering nanocurvature interfaces featuring asymmetric bimetallic sites, achieving selective transformation of CO2 to high-value C2 chemicals.