Porous high-entropy alloy coatings as highly efficient electrocatalysts for electrocatalytic water splitting

Developing highly efficient and stable non-noble metal electrocatalysts has always been a grand challenge for water splitting. Herein, the promising and highly efficient porous high entropy alloy (HEA) coatings is fabricated through the plasma spraying, which could be favorable to solve the above issues. Abased on the synergistic effect of different metals and the porous structure within the HEA coatings, it can provide the superior catalytic activities. Hence, the CoCrFeNiMo catalyst displays a low overpotential of 273 mV (for oxygen evolution reaction, OER) at 100 mA cm−2 in 1.0 M KOH electrolyte. As hydrogen evolution reaction (HER) catalysts, the CoCrFeNiMo presents a small overpotential. When the catalysts can be utilized to the overall water splitting, it delivers an excellent durable for 24 h. DFT result shows that CoCrFeNiMo is conducive to the hydrogen adsorption/desorption process, and it can enhance the transformation of *O to *OOH and improve the OER performance. This study not only offers a universal method to prepare high performance electrocatalysts, but also demonstrates the great potential of HEA coatings in energy conversion fields.