Development of a highly stable and active non-precious anode electrocatalyst for oxygen evolution reaction in acidic medium based on nickel and cobalt-containing antimony oxide

Abstract

The electrocatalysts anodes using base metals on titanium substrate by sol–gel method were synthesized as an alternative due to the scarcity of noble metals, such as iridium and ruthenium. For this purpose, the cobalt antimonate and nickel–cobalt antimonate stable electrocatalysts to carry out the oxygen evolution reaction (OER) were developed. LSV showed that the cobalt antimonate electrocatalyst has an intrinsic potential of 1.615 V vs. RHE. For the cobalt antimonate electrocatalyst, the potential corresponding to the current density of 10 mA.cm−2 is 1.791 V vs. RHE. The stability of all synthesized anodes at a current density of 10 mA.cm−2 was at least 200 h (more than 8 days) while the CoSb2Ox electrocatalyst displayed a superior lifetime for at least 650 h (more than 27 days) at a current density of 100 mA.cm−2. According to the EIS data at the potential of 1.791 V vs. RHE, the nickel–cobalt antimonate had the lowest charge transfer resistance (Rct) of 4 Ω.cm2. The combination of the above results confirms the capability of the proposed anode as a substitute for precious ones.