Ampere-level glycerol electrooxidation enabled by oxygen vacancy-riched crystalline/amorphous Co₃O_4-x/ZrO_2-x...

The development of high-performance electrocatalysts for the valorization of surplus glycerol into high-value-added chemicals using renewable electricity is of great significance for a sustainable economy. However, significant challenges remain in maintaining efficient production of target products at ampere-level current densities. Herein, we successfully constructed crystalline/amorphous Co₃O_4-x@ZrO_2-x heterostructured nanosheets in situ on nickel foam (NF) substrate. This unique architecture exposes abundant active sites while the coupled crystalline/amorphous electronic interaction enhances interfacial charge transport, thereby endowing the catalyst with exceptional performance for glycerol electrooxidation to formate. Remarkably, the optimized Co₃O_4-x@ZrO_2-x/NF achieves an ampere-level current density of 1 A cm^-2 at a low potential of 1.5 V vs. RHE, while delivering an impressive Faradaic efficiency of formate over 90 % across a wide range of 0.4-1.0 A cm^-2. In situ spectroscopic studies reveal that the crystalline/amorphous heterostructure facilitates the dynamic reconstruction of active species and significantly promoted the reaction kinetics for glycerol oxidation. Furthermore, when employed in a two-electrode system, the electrolyzer demonstrates efficient Faradaic efficiency of H₂ (nearly 100 %) and formate yield (11.99 mmol h^-1 cm^-2 at 1 A cm^-2), as well as exceptional stability over 100 h at 100 mA cm^-2.