High‐entropy oxide‐supported platinum nanoparticles for efficient hydrogen evolution reaction

Abstract High‐entropy oxides (HEOs) are a new class of single‐phase structures with unique electronic and catalytic properties; therefore, it is worthwhile to explore their applications in electrocatalysis. In this study, a Pt/(FeCoNiCrAl) 3 O 4 nanohybrid using HEO as a support was developed as an efficient catalyst for the hydrogen evolution reaction (HER). Pt/(FeCoNiCrAl) 3 O 4 exhibited high HER activity with a low overpotential of 22 mV at 10 mA·cm −2 , outperforming other binary, ternary, and quaternary supports. The HER activity of Pt/(FeCoNiCrAl) 3 O 4 was higher than that of a commercial Pt/C with a significantly lower Pt loading. The catalyst exhibited good activity and long‐term stability (60 h) in an electrolytic water‐splitting device. This good activity can be attributed to the fact that the introduction of Pt effectively facilitates electronic interactions between Pt and the HEO. In addition, the HEO substrate was more favorable for dispersing Pt particles, optimizing the electrochemical specific surface area, and significantly reducing the charge resistance of the HER. This study extends the application of HEOs in electrocatalysis and demonstrates the promising prospects of HEOs as supports for electrocatalysts.