Hydrogen Storage Technologies: Materials Innovation and System-Level Challenges for a Carbon-Neutral Future

Abstract

This review provides an assessment of hydrogen storage pathways and identifies strategies for energy applications. Technologies examined include compressed gaseous storage, liquid hydrogen (LH₂), cryo-compressed systems, solid-state hydrides, chemical carriers, and adsorption-based materials, evaluated in terms of storage performance, safety, economic feasibility, and scalability. Compressed and LH₂ systems are mature options but are constrained by energy penalties, boil-off losses, leakage risks, and infrastructure costs. Solid-state hydrides offer storage density and improved safety, yet deployment remains limited by slow sorption kinetics, elevated desorption temperatures, and structural degradation during cycling. Chemical carriers, including ammonia, methanol, formic acid, and liquid organic hydrogen carriers (LOHCs), provide diverse hydrogen densities and established production routes; however, infrastructure requirements vary among carrier types. Ammonia requires corrosion-resistant materials and pressure–temperature conditions, whereas LOHCs depend on bidirectional logistics networks. Catalyst degradation, toxic byproducts, and energy-intensive regeneration continue to impede adoption. Adsorption-based materials, including metal–organic frameworks, covalent organic frameworks, and carbon nanostructures, demonstrate hydrogen uptake under cryogenic conditions but remain limited by costly synthesis and low-temperature operation. The review highlights the advancement in nanostructured materials, non-precious metal catalysts, hybrid storage systems, and near-ambient adsorption technologies, while outlining research priorities needed to achieve safe, efficient, scalable, and economically viable hydrogen storage worldwide.