Frustrated Lewis pairs photocatalyst for visible light-driven reduction of CO to multi-carbon chemicals

Abstract

Photocatalytic reduction of carbon monoxide (CO), an increasingly available and low-cost feedstock that could benefit from CO₂ reduction, to high value-added multi-carbon chemicals, is significant for desirable carbon cycling, as well as high efficiency conversion and high density storage of solar energy. However, developing low cost but highly active photocatalysts with long-term stability for CO coupling and reduction remains a great challenge. Herein, by density functional theory (DFT) computations and taking advantage of the frustrated Lewis pairs (FLPs) concept, we identified a complex consisting of single boron (B) atom decorated on the optically active C₂N monolayer (i.e., B/C₂N) as an efficient and stable photocatalyst for CO reduction. On the designed B/C₂N catalyst, CO can be efficiently reduced to ethylene (C₂H₄) and propylene (C₃H₆) both with a free energy increase of 0.22 eV for the potential-determining step, which greatly benefits from the pull–push function of the B–N FLPs composed of the decorating B atom and host N atoms. Moreover, the newly designed B/C₂N catalyst shows significant visible light absorption with a suitable band position for CO reduction to C₂H₄ and C₃H₆. All these unique features make the B/C₂N photocatalyst an ideal candidate for visible light driven CO reduction to high value-added multi-carbon fuels and chemicals.