Size-Controllable PtPdRuRhCuMo High-Entropy Alloy Nanoparticles for Electrocatalytic Ethylene Glycol Oxidation

High-entropy alloy nanoparticles (HEA NPs) have emerged as a promising core material for designing efficient electrocatalysts, owing to their unique multi-element synergistic effects and structural stability. However, precise control over their morphology and composition remains challenging. In this study, well-dispersed and uniform PtPdRuRhCuMo HEA NPs were successfully synthesized via a facile solvothermal method, leveraging the distinct morphology-directing effects of CTAB and CTAC. The resulting catalysts, particularly the HEA-1 sample (using CTAB as the surfactant), exhibited exceptional electrocatalytic performance toward the alkaline ethylene glycol oxidation reaction (EGOR), achieving a mass activity of 2.4 A mg-1, which significantly surpasses that of commercial Pt/C (1.25 A mg-1). More importantly, the HEA-1 catalyst possesses excellent long-term cyclic stability, retaining 50% of its activity after 10 hours of continuous testing, attributed to the strong electronic interactions between the multi-metal components and the structural integrity of the nanoparticles. This work not only provides a new strategy for the precise control of HEA nanostructures but also advances their potential application in direct alcohol fuel cells and other energy conversion systems.