High entropy design endows spinel compounds with excellent bifunctional catalysis for hydrogen production from water electrolysis

Promoting the use of hydrogen energy is considered an effective strategy to address current energy and environmental challenges. Developing efficient and cost-effective bifunctional catalysts is crucial for advancing hydrogen production. In this study, novel high-entropy spinel oxide (FeCoNiCrZnCu)₃O₄ was successfully synthesized via a microwave hydrothermal method as a catalyst for water electrolysis under alkaline conditions. The results demonstrate that the high-entropy strategy is an effective approach to enhancing the oxygen vacancy content in spinel oxides. Additionally, compared to non-high-entropy materials, exhibited an increased specific surface area, indicating that the high-entropy strategy also positively impacts the surface morphology. Benefiting from the increased oxygen vacancy content and the synergistic effect of multi-metal cations, (FeCoNiCrZnCu)₃O₄ showed exceptional bifunctional catalytic performance in water electrolysis. At a current density of 10 mA cm⁻², the corrected hydrogen evolution overpotential and oxygen evolution overpotential were only 133 mV and 357 mV, respectively. This work provides valuable insights into the application of high-entropy spinel materials in hydrogen production via water electrolysis.