No abstract

The development of efficient, durable, and affordable electrocatalysts is critical for the advancement of a hydrogen economy, particularly in alkaline media. In this study, we propose CoCrFeNi and CoCrFeNiMo high entropy alloys (HEAs) powders as bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). While there is a performance gap compared to Pt/C, the prepared samples exhibit relatively good electro-catalytic activity with overpotentials of 156.7 mV and 160.5 mV for HER at 10 mA cm À 2 in a 1.0 M KOH solution, respectively. Notably, the CoCrFeNiMo catalyst demonstrates significantly higher OER activity than commercial RuO 2 with an overpotential of 390 mV at 50 mA cm À 2 , and delivers a cell voltage of 1.86 V at a current density of 10 mA cm À 2 for water splitting.