Non-precious nickel-based catalysts for hydrogen oxidation reaction in alkaline electrolyte

Abstract

With the rapid development of anion exchange membranes, researchers began to shift their attention from proton exchange membrane fuel cells (PEMFCs) with acid electrolytes to anion exchange membrane fuel cells (AEMFCs) with alkaline electrolytes. Non-precious metal catalysts such as Fe-N-C catalysts are available for ORR at the cathode in alkaline electrolytes. But at the anode, the catalytic reaction kinetics of Pt catalysts in alkaline media is two orders of magnitude slower than that in acid media, which prompts researchers to develop new low-cost and high-efficient non-precious metal catalysts for HOR. Up to date, the typical non-precious metal catalysts for HOR are Ni-based materials. In this minireview, we firstly introduced the elementary steps of HOR and the important activity parameters for a HOR catalyst. Secondly, we briefly describe the performance of various Ni-based HOR catalysts reported in recent years.