Electrocatalytic behaviour of Co–Fe–Ni–Cr–V–Zr eutectic high entropy alloy

Abstract

The electrocatalytic behaviour of bulk eutectic high entropy alloys (EHEAs) has rarely been explored despite possessing large electrocatalytic active sites. In this work, bulk EHEA has been investigated as an electrocatalyst considering hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The results depict good kinetic behaviour, evidenced by a low Tafel slope of 251 mV dec⁻¹ and an overpotential of −0.415 V to achieve −0.01 A cm⁻² for HER. Similarly, for OER, a low Tafel slope of 115 mV dec⁻¹ and overpotential of 1.5879 V to achieve 0.01 A cm⁻², with good long-term electrolysis stability for 24 h are achieved. The electrochemically active surface area of EHEA catalyst for both HER and OER is 0.033 and 0.0727 cm², respectively.