Engineering of Self-Supported Electrocatalysts on a Three-Dimensional Nickel Foam Platform for Efficient Water Electrolysis

Economical water electrolysis requires highly active non-noble electrocatalysts to overcome the sluggish kinetics of the two half-cell reactions, oxygen evolution reaction, and hydrogen evolution reaction. Although intensive efforts have been committed to achieve a hydrogen economy, the expensive noble metal-based catalysts remain under consideration. Therefore, the engineering of self-supported electrocatalysts prepared using a direct growth strategy on three-dimensional (3D) nickel foam (NF) as a conductive substrate has garnered significant interest. This is due to the large active surface area and 3D porous network offered by these electrocatalysts, which can enhance the synergistic effect between the catalyst and the substrate, as well as improve electrocatalytic performance. Hydrothermal-assisted growth, microwave heating, electrodeposition, and other physical methods (i.e., chemical vapor deposition and plasma treatment) have been applied to NF to fabricate competitive electrocatalysts with low overpotential and high stability. In this review, recent advancements in the development of self-supported electrocatalysts on 3D NF are described. Finally, we provide future perspectives of self-supported electrode platforms in electrochemical water splitting.