Uncovering Atomic-Scale Stability and Reactivity in Engineered Zinc Oxide Electrocatalysts for Controllable Syngas Production

In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H-2 and CO during electrochemical CO2 reduction reactions (CO2RR). The designed ZnO achieves an H-2/CO ratio of approximate to 1 with a large current density (j) of 40 mA cm(-2) during long-term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO2RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal-oxides can be used as guidelines to develop active catalysts for syngas production for renewable power-to-X to generate a range of fuels and chemicals.