Understanding factors affecting storage capacity and reproducibility in realistic ambient-temperature hydrogen physisorption

Abstract

Physisorption-based materials such as metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and porous carbons have been extensively studied for hydrogen storage due to their high surface areas and tunable pore structures. While these materials show high hydrogen uptake at cryogenic temperatures, storage at ambient conditions (0–50 °C) remains challenging due to weaker binding energies. To improve ambient-temperature performance, various approaches, including metal doping, pore engineering, and functionalization, have been explored. However, some reported ambient-temperature uptake values approach those seen only at cryogenic conditions, raising concerns about measurement errors and reproducibility. This review highlights these challenges and stresses the need for standardized experimental protocols and transparent data sharing. By minimizing errors and fostering reproducibility, future research can accelerate the development of practical, scalable hydrogen storage technologies operable at near-ambient conditions.