Hydrogen storage via adsorption: A review of recent advances and challenges

Hydrogen is a promising energy carrier, and its demand for various applications is rising, projected to reach nearly USD 309.17 billion by 2030. Unfortunately, finding efficient and safe storage options precludes its effective utilization. Notwithstanding, among various hydrogen storage methods, adsorption on porous materials has shown prospects lately with the advantage of high volumetric density, low operating pressure, and reversibility. Among many adsorbents, new trends are MXenes, borophene-based, hybrids, and magnetic materials. While borophene-based have selective characteristics and thermodynamic advantages, hybrid materials offer the opportunity to augment the individual adsorbent limitations. MXenes, on the other hand, facilitate a phenomenon called “nanopump effect” for efficient hydrogen storage. Generally, the adsorption-base storage mechanism encompasses physisorption, chemisorption, and Kubas-type interactions. It also extends to the nanopump and force field effects. Accordingly, this review provides recent advances and challenges in hydrogen storage via adsorption on various surfaces. These include the principles of hydrogen adsorption, various adsorbents used, and the interplay between adsorbent design and storage performance (thermodynamics, kinetics, and isotherms). Additionally, a variety of in situ and ex situ characterization techniques and the potential of simulation and modeling, including machine learning, will be explored. Finally, it highlights current limitations and future perspectives of adsorption as a technology for hydrogen storage.