NiFe2O4: harnessing catalytic potential in water splitting

NiFe₂O₄ is a potential catalyst for energy conversion and storage, owing to its electrical conductivity, catalytic activity, and stability. The system's compatibility with various synthesis procedures and the ability to tune its properties through versatile techniques including doping and surface modifications have attracted significant attention for water splitting applications. Herein, we comprehensively detail the catalytic characteristics of NiFe₂O₄-based structures, particularly useful for water splitting reactions (hydrogen evolution reaction (HER) and oxygen evolution reaction (OER)) and also discuss the possible mechanisms of water splitting reactions on NiFe₂O₄-based systems. The modulation of characteristics of the system by different synthesis procedures and tuning of its characteristics via various strategies such as defect engineering, surface engineering, heterojunction formation, and non-metal incorporation are important in designing and developing related systems for catalytic applications. The optical features of the system promise its applicability in photocatalytic reactions while good conductivity and magnetic properties amplify the electrocatalytic reactions. There are many hurdles in implementing the system for the photocatalytic water splitting as well as for long-term electrochemical applications. This review provides a straightforward direction to researchers to choose suitable methods for character tuning and to identify the missing areas related to the application of the material and its future scope.