Silicon nanostructures for solid-state hydrogen storage: A review

Sustainable development of hydrogen energy is a prime concern to address the rising energy demand and the global energy problem since the hydrogen economy is reliable for clean and carbon-free energy carriers. Despite well-established commercial sector technologies, boil-off losses, explosive nature, and leakage risk still exist with compressed and liquefied storage. One of the significant remedies, solid-state hydrogen storage, improves bulk density and gravimetric capacity and addresses safety concerns. The rising popularity of light and heavy fuel cell vehicles is projected to promote the advancement of onboard solid-state hydrogen technology. The present review focuses on the importance of existing porous materials, polymers, metal, and complex metal hydrides for solid-state hydrogen storage and the dominance of Si nanostructures (SiNSs). The fabrication techniques of porous silicon, porous silicon nanowires, and Si quantum dots are accentuated. The review provides insights into the hydrogen-assisted properties, regularities, the importance of hydrogen energy on automobiles for alleviating climate change phenomena, and the application of SiNSs for hydrogen storage with other transition and alkali earth materials to overcome the issues. It highlights the importance of catalysts in resolving the existing reversibility and desorption issues associated with hydrogen energy storage. Different popular desorption techniques considering the pore dimensions are discussed. The evaluation may enable energy providers and Si-based fuel cells to be better customized, promoting the development of the hydrogen energy economy.