Asymmetric Cu-N-La Species Enabling Atomic-Level Donor-Acceptor Structure and Favored Reaction Thermodynamics for Selective CO Photoreduction to CH.

Photocatalytic CO reduction into ideal hydrocarbon fuels, such as CH , is a sluggish kinetic process involving adsorption of multiple intermediates and multi-electron steps. Achieving high CH activity and selectivity therefore remains a great challenge, which largely depends on the efficiency of photogenerated charge separation and transfer as well as the intermediate energy levels in CO reduction. Herein, we construct La and Cu dual-atom anchored carbon nitride (LaCu/CN), with La-N and Cu-N coordination bonds connected by Cu-N-La bridges. The asymmetric Cu-N-La species enables the establishment of an atomic-level donor-acceptor structure, which allows the migration of electrons from La atoms to the reactive Cu atom sites. Simultaneously, intermediates during CO reduction on LaCu/CN demonstrate thermodynamically more favorable process for CH formation based on theoretical calculations. Eventually, LaCu/CN exhibits a high selectivity (91.6 %) for CH formation with a yield of 125.8 μmol g , over ten times of that for pristine CN. This work presents a strategy for designing multi-functional dual-atom based photocatalysts.