Latest developments in structural frameworks and synergistic effects of Ni-based MOFs for efficient electrocatalytic hydrogen generation: An overview

The continuous rise in energy demand globally and the detrimental effects of environmental change, the need for a sustainable energy source has become more pressing than ever. Hydrogen has emerged as a promising green energy source and a viable substitute to fossil fuels, owing to its high energy density and no carbon emissions. The HER is a key step in the process of hydrogen generation via water electrolysis. Among the various electrocatalysts explored for HER, considerable interest has been shown in nickel-based MOFs because of their structural tunability, high surface area, numerous electroactive sites, and cost efficiency. Unlike previous reviews that mainly discuss structural aspects or compositional tuning in isolation, this work uniquely integrates both structural engineering strategies and synergistic effects, thereby providing a more comprehensive perspective on Ni-MOFs for HER. The current review focuses on recent developments in the structural design of Ni-MOFs, including ligand modification, bimetallic and trimetallic integration, morphological engineering, and post-synthetic strategies. Furthermore, it discusses the synergistic effects, such as electronic modulation, defect engineering, and interfacial coupling that enhance catalytic efficiency and stability. Finally, existing bottlenecks and forthcoming opportunities are outlined. This provides guidance for the rational development of highly efficient Nickel-MOF-based HER electroactive catalysts for commercializing hydrogen as a sustainable energy solution.