Stability challenges and opportunities of NiFe-based electrocatalysts for oxygen evolution reaction in alkaline media

Water splitting is a critical process for the production of green hydrogen, contributing to the advancement of a circular economy. However, the application of water splitting devices on a large scale is primarily impeded by the sluggish oxygen evolution reaction (OER) at the anode. Thus, developing and designing efficient OER catalysts is a significant target. NiFe-based catalysts are extensively researched as excellent OER electrocatalysts due to their affordability, abundant reserves, and intrinsic activities. However, they still suffer from long-term stability challenges. To date, few systematic strategies for improving OER durability have been reported. In this review, various advanced NiFe-based catalysts are introduced. Moreover, the OER stability challenges of NiFe-based electrocatalysts in alkaline media, including iron segregation, structural degradation, and peeling from the substrate are summarized. More importantly, strategies to enhance OER stability are highlighted and opportunities are discussed to facilitate future stability studies for alkaline water electrolysis. This review presents a design strategy for NiFe-based electrocatalysts and anion exchange membrane (AEM) electrolyzers to overcome stability challenges in OER, which also emphasizes the importance of long-term stability in alkaline media and its significance for achieving large-scale commercialization.