A Review on Functional Materials for Hydrogen Storage

ABSTRACT The need for safe, cost‐effective, lightweight, and energy‐efficient hydrogen storage in both mobile and stationary applications has led to the development of novel materials with functional properties. Effective hydrogen storage materials possess characteristics such as high capacity per unit mass, minimal energy loss during charging and discharging, efficient kinetics, stability against O 2 , recyclability at low cost, and significant safety features. Solid‐state storage has emerged as a preferred technique for hydrogen storage compared to pressurized gas and liquefaction processes, primarily due to its ability to achieve high storage capacities while maintaining safe operating conditions. Metal hydrides, such as MgH 2 , exhibit a hydrogen storage capacity of up to 7.6 wt.%, while complex hydrides like LiBH 4 can store up to 18.5 wt.% hydrogen. Adsorption‐based nanostructured materials, such as activated carbon and metal–organic frameworks, offer high surface areas for hydrogen uptake, with capacities reaching 5–7 wt.% at cryogenic temperatures. This review critically evaluates recent advancements in hydrogen storage materials, highlighting breakthroughs in kinetics enhancement, thermodynamic stability, and material reversibility. Compared to previous studies, this work consolidates key developments and identifies future research directions for optimizing hydrogen storage performance in real‐world applications. This review provides in‐depth insights into the mechanisms of functional solid material for hydrogen storage and explores the factors influencing their performance. Additionally, various applications of hydrogen storage across different sectors are discussed, highlighting the potential of these storage technologies in practical settings.