Surface Structure Engineering of FeNi-Based Pre-Catalyst for Oxygen Evolution Reaction: A Mini Review

Abstract

Oxygen evolution reaction (OER) is a significant half-reaction for water splitting reaction, and attention is directed to the high-performance non-precious catalysts. Iron nickel (FeNi)-based material is considered as the most promising pre-catalyst, that will be transferred to the real active phase in the form of high valence state metal species. Even so, the catalytic performance is largely influenced by the structure and morphology of the FeNi pre-catalysts, and lots of work has been done to optimize and tune the structure and chemical environment of the FeNi- based pre-catalysts so as to increase the catalytic performance. Herein, based on our work, a mini review is proposed for the surface structure engineering of FeNi-based pre-catalyst for OER. The reaction mechanism of alkaline OER is firstly presented, and then the strategies in surface engineering of FeNi-based pre-catalyst for improving OER performance are discussed in terms of heteroatom doping, surface composition modification, selective structural transformation, surface chemical state regulation, heterostructure construction, and support effect. It can be concluded that the surface structure, morphology, and the chemical states of Fe/Ni in the system will significantly influence the final catalytic performance, though all of them were transferred into the active phase state of high valence state metal species. In other words, the catalytic performance of FeNi-based catalysts is also determined by the property of their pre-catalysts. To carefully design and maximize the synergistic effect of Fe and Ni is necessary to boost the catalytic performance. We hope this topic will be a good and timely complement to the study of FeNi-based catalysts for OER in the water-splitting technique.

Keywords

FeNi-based catalyst / surface structure engineering / oxygen evolution reaction / water splitting reaction / catalysis

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