This study investigates the use of high-entropy oxides (HEOs) as supports for platinum nanoparticles (Pt) to enhance their performance in the hydrogen evolution reaction (HER). The authors developed a Pt/(FeCo-NiCrAl)₂O₄ nanohybrid using a sol-gel method to synthesize HEO nanoparticles and impregnation to load Pt nanoparticles. The resulting catalyst exhibited superior HER activity with a low overpotential of 22 mV at 10 mA·cm⁻², outperforming other binary, ternary, and quaternary supports. The catalyst also demonstrated good long-term stability (60 hours) in an electrolytic water-splitting device. The enhanced performance is attributed to the effective electronic interactions between Pt and the HEO, which optimize the electrochemical specific surface area and reduce charge resistance. This study highlights the potential of HEOs as effective supports for electrocatalysts, extending their application in clean energy technologies.This study investigates the use of high-entropy oxides (HEOs) as supports for platinum nanoparticles (Pt) to enhance their performance in the hydrogen evolution reaction (HER). The authors developed a Pt/(FeCo-NiCrAl)₂O₄ nanohybrid using a sol-gel method to synthesize HEO nanoparticles and impregnation to load Pt nanoparticles. The resulting catalyst exhibited superior HER activity with a low overpotential of 22 mV at 10 mA·cm⁻², outperforming other binary, ternary, and quaternary supports. The catalyst also demonstrated good long-term stability (60 hours) in an electrolytic water-splitting device. The enhanced performance is attributed to the effective electronic interactions between Pt and the HEO, which optimize the electrochemical specific surface area and reduce charge resistance. This study highlights the potential of HEOs as effective supports for electrocatalysts, extending their application in clean energy technologies.