Dehydrogenation Thermodynamic and Kinetic Challenges of Mg-Ni-Based Alloy Hydrides

Solid-state hydrogen storage stands as a pivotal, safe, and efficient solution for the future hydrogen economy. Among diverse hydrogen storage systems, Mg-Ni-based alloy hydrides are recognized as cornerstone materials. However, their practical application is hindered by two core challenges: the high thermodynamic stability of the hydride phase and sluggish reaction kinetics. This review systematically deconstructs various core strategies to address these two bottlenecks. For thermodynamic control, we delve into chemical bond reconstruction through advanced alloying and nanostructure engineering to facilitate low-temperature dehydrogenation. For kinetic optimization, we trace the evolution process of catalysis, starting from the classic “hydrogen pump” mechanism and the newly unveiled “burst effect,” which lays a foundational framework for the rational design of advanced catalyst systems, including single-atom, cluster, and nano-sized catalysts to achieve enhanced kinetic performance. Crucially, this review charts the field's paradigm shift from empirical “trial-and-error” modification to targeted “rational design.” We advocate for the integration of frontier tools of high-throughput computation, in situ characterization, and data-driven discovery to realize synergistic regulations of both the dehydrogenation thermodynamics and kinetics in Mg-Ni-based alloy hydrides. © 2026 The Author(s). Rare Metals published by John Wiley & Sons Australia, Ltd on behalf of Youke Publishing Co., Ltd.