Improving selectivity of CO reduction: Via reducing the coordination of critical intermediates

Electrochemical reduction of CO to value-added chemicals has attracted great interest. A challenge is to improve the selectivity towards C₂ chemicals and suppress the formation of CH₄ that is less valuable. Here using first-principles calculations, we show that CH₄ formation can be suppressed via reducing the coordination of critical intermediates. This is demonstrated through the example of double metal atoms anchored on carbon nitride (C₂N), which can efficiently catalyze the production of C₂ chemicals, without CH₄. The high selectivity originates from the weakened binding of the ∗CH/∗CH₂ intermediate with the metal atoms due to the reduced coordination, resulting in coupling with neighboring ∗CO and forming a C₂ intermediate that can further transform into C₂ products. Our work provides a new strategy to improve the selectivity of CO reduction and also suggests a promising candidate.