Review on Tuning the Dimensionality and Geometry of Metal Nitride and Boride Nanostructures for Enhanced Hydrogen Storage: Advances and Outlook

Hydrogen is an abundant and clean energy carrier, yet efficient and safe storage remains a major obstacle to the realization of a sustainable hydrogen economy. Conventional storage technologies based on high-pressure compression and cryogenic liquefaction still struggle to satisfy the operational safety and economic viability. Solid-state hydrogen storage offers a promising alternative; however, achieving reversible hydrogen adsorption under near-ambient conditions with sufficiently high storage capacity remains a significant challenge. In this minireview, we demonstrate that nanostructuring, particularly through controlling the dimensionality and geometry of metal-nitride- and boride-based nanostructures, provides an effective strategy for tuning hydrogen adsorption energies into the optimal range from approximately −0.2 to −0.6 eV/H 2 required for reversible storage. We systematically discuss how dimensionality, curvature, pore geometry, and local coordination environments influence hydrogen adsorption mechanisms, active-site stability, and storage performance by regulating charge transfer, orbital hybridization, local electric fields, and hydrogen-binding strength. We also analyze the critical roles of strain engineering, defect engineering, and metal-site stabilization in optimizing adsorption/desorption thermodynamics and suppressing metal clustering. These insights establish a comprehensive structure–property relationship framework for balancing storage capacity, adsorption energetics, reversibility, and kinetics.