Cooperative Atomic Palladium Site and Island-Distributed S-Scheme Heterostructure for Photocatalytic C₂H₆ Production

Abstract

The CO2 reduction reaction (CO2RR) to produce C2 products relies on the synergy between the C1 generation site and the C–C coupling site within the photocatalytic system. However, yields are often limited by inadequate C1 precursor production, inefficient multielectron transport, and weak C1 adsorption at the C–C coupling site. In this study, we developed a highly efficient photocatalytic system that achieved remarkable conversion of CO2 to C2H6 by integrating Pd single atomic sites and island-distributed PdO nanoparticles onto phosphorus-modified BiOCl (PdO/BOCP-Pd1). This system exhibited a prominent C2H6 yield of 215.6 μmol g–1 h–1 and a selectivity of 97.5%, maintaining its performance with negligible decay over a minimum duration of 200 h, representing the top-level photocatalytic performance of reported photocatalysts. Both experimental and theoretical results confirm that the Pd1 site in the PdO/BOCP-Pd1 catalyst significantly enhances the availability of local CO. Its distinctive S-scheme charge transfer mode promotes the formation of electron-rich PdO sites. Thanks to the superior CO adsorption capacity of PdO, these electron-rich PdO sites can serve as efficient C–C coupling sites after adsorbing CO, ultimately leading to the highly efficient production of C2H6. This study provides insight into designing multisite cooperative photocatalysts for superior CO2RR to C2 products.