Defect Engineering in Nanomaterials: A Pathway to Enhanced Hydrogen Storage Performance

Hydrogen, a green source of energy, is nowadays attracting researchers a lot due to its abundance, high energy density, and zero carbon emission properties. A number of methods have been discovered for producing hydrogen, but the challenges in storing hydrogen are limiting its use as a primary fuel. For practical uses, conventional storage technologies such as compressed hydrogen and liquid hydrogen are too expensive and have some major drawbacks, like high energy consumption and cryogenic infrastructure. Overcoming these limitations, nanostructured materials are very promising candidates for storing hydrogen, taking advantage of high theoretical capacities and their unique properties. However, these materials also go through different types of damage during hydrogen cycling. Different damages, such as structural damages, sluggish kinetics, low hydrogen adsorptions, laser exposure issues, defects in multiwalled carbon nanotubes (MWCNTs), and poor reversibility, cause limited storage capacity of the total hydrogen storage system. This review article summarizes the limitations of nanostructured materials during hydrogen charging and discharging, concentrating on the types of failures that occurred and their effects on storage performance. However, new approaches such as defect engineering and more advanced synthesis methods have begun to address some of these damages in recent years and use defects to enhance the storage performance. The results emphasize the urgent need to develop tough and durable nanostructured materials for hydrogen storage systems. The environments should allow them to develop cheaper and more effective materials with more durability and reversibility. This review provides directions to researchers on how to develop the next generation of hydrogen storage technologies with the help of nanotechnology.