In Operando Identification of In Situ Formed Metalloid Zinc Active Sites for Highly Efficient Electrocatalyzed Carbon Dioxide Reduction.

Electrochemical CO -to-CO conversion provides a possible way to address problems associated with the greenhouse effect; however, developing low-cost electrocatalysts to mediate high-efficiency CO reduction remains a challenge on account of the limited understanding of the nature of the real active sites. Herein, we reveal the Zn metalloid sites as the real active sites of stable nonstoichiometric ZnO structure derived from Zn P O through operando X-ray absorption fine structure analysis in conjunction with evolutionary-algorithm-based global optimization. Furthermore, theoretical and experimental results demonstrated that Zn metalloid active sites could facilitate the activation of CO and the hydrogenation of *CO , thus accelerating the CO -to-CO conversion. Our work establishes a critical fundamental understanding of the origin of the real active center in the zinc-based electrocatalysts for CO reduction reaction.