Simultaneously Engineering the Amorphous Phase and Branch Morphology of High‐Entropy Alloy Nanomaterials for Enhanced Ethylene Glycol Oxidation

ABSTRACT High entropy alloy (HEA) nanomaterials have emerged as an intriguing class of catalysts for diverse catalytic applications, yet engineering their morphology and/or crystal phase remains challenging. Herein, we successfully achieve the simultaneous engineering of both the amorphous phase and branch morphology of PdCuNiCoFe HEA nanomaterials. Excitingly, the synthetic protocol is effectively extended to synthesizing a library of amorphous Pd‐based nanobranches, including binary, ternary, and quaternary alloys. When employed as catalysts for ethylene glycol oxidation reaction (EGOR), the amorphous PdCuNiCoFe HEA achieves superior activity and selectivity of glycolic acid approaching 98.6%, and enables a remarkable overpotential drop of 774 mV at 100 mA cm ‒2 in EGOR‐assisted water electrolysis. Mechanistic investigation demonstrates the excellence of amorphous PdCuNiCoFe HEA in suppressing C−C cleavage, facilitating * OH/ * EG adsorption, and lowering the free energy requirement for glycolic acid production. This study offers a promising means to rationally engineer the morphology and phase of HEAs for enhanced electrocatalysis.