Nanostructured Transition Metal Electrocatalysts on Nickel Foam: Design and Performance for Alkaline OER

Abstract

Hydrogen generation through electrochemical water splitting offers a viable and sustainable solution for future energy needs. However, the oxygen evolution reaction (OER) of this process is hindered by complex kinetics, thereby require high-performance, affordable and stable electrocatalysts. Earth-abundant alternatives engineered using three-dimensional (3D) nickel foam (NF) as substrate with interconnected porous architecture offer a large electrochemically active surface area and an exceptional electrical conductivity. Herein, we systematically explore recent developments in nanostructured transition metal (TM)-OER electrocatalysts directly synthesized on 3D NF including chalcogenides, oxides, hydroxides, layered double hydroxides, phosphides, borides, nitrides, and alloys. Key structural modification strategies, such as morphology control, heterojunction engineering, surface/interface tuning, elemental doping, vacancy formation, and electronic/ion modulation are focused, critically examining their effects on morphology, efficiency, durability, and real-world applicability. Recent advances highlight that beyond compositional tuning and nanostructuring, the coordination effect and the deliberate modulation of active centers with NF play a key role in governing the efficiency, reaction pathways, and durability. This review systematically discusses the effects of coordination geometry changes, metal-oxygen bond interactions, and interfacial coordination between active species and NF collectively contributing to improved OER performance. The coordination engineering can tune electronic structure, facilitate the generation of high-valence active intermediates, and enhance charge transfer dynamics. Thus, synthesis control, structure-property relationships, performance enhancement, and mechanistic understanding of catalytic behavior are crucial. Finally, the review highlights existing challenges and offers future research directions where coordination design principles can guide the rational development of next-generation NF-supported OER electrocatalysts leading to industrial-scale hydrogen production.