• • Pd20Pt20Cu20Ni20P20 HEMG achieves a current density of 10 mA cm−2 at an overpotential of 23 mV for hydrogen evolution reaction (HER) in 0.5 M H2SO4, outperforming commercial Pt/C (31 mV) and demonstrating enhanced intrinsic activity.
• • For methanol oxidation reaction (MOR), the HEMG exhibits a mass activity of 1.2 A mg−1Pd, which is 2.4 times higher than that of Pd/C (0.5 A mg−1Pd), indicating superior utilization of noble metals.
• • The HEMG retains 92% of its initial current density after 10,000 potential cycles in HER, whereas crystalline high-entropy alloy and metallic glass counterparts degrade to 78% and 85%, respectively, highlighting its exceptional electrochemical stability.
• • The HEMG's amorphous structure and high configurational entropy result in a broader distribution of active sites, as evidenced by a lower Tafel slope of 38 mV dec−1 for HER compared to 45 mV dec−1 for the crystalline HEA, signifying faster reaction kinetics.