Orbital-Level-Directed Selective CO₂-to-C₂H₄ Photoreduction via Se Vacancies and Plasmonic Pt.

Abstract

The photocatalytic reduction of CO₂ to C₂ products with high selectivity under visible light remains a grand challenge primarily due to the high-energy barriers and kinetic complexities of C-C coupling. The current strategies primarily concentrate on augmenting the number of carriers to activate the multielectron transfer system, often overlooking the mechanism by which the coupling effect of catalyst surface energy influences intermediates. Herein, we report a strategy that synergizes vacancies and plasmonic Pt to steer the high energy of key intermediates for selective C₂ production. The constructed catalyst achieves an exceptional ethylene yield of 86.81 μmol·g^-1·h^-1 with near-unity selectivity (∼100%), significantly outperforming most reported systems. Concurrently, experimental findings indicate that the elevation of the substrate electron orbitals is positively correlated with the coupling strength of the CO intermediate. This work not only showcases a high-performance photocatalytic approach for the reduction of CO₂ to C₂ but also deciphers the fundamental role of electron orbital energy levels in steering the selectivity of C₂ products.