Effects of carbon on hydrogen storage performances of hydrides

The development of hydrogen storage materials with high performance has been attracting considerable attention in recent years. Magnesium hydride, alanates, borohydrides and ammonia borane are the most promising candidates due to their high hydrogen capacity, but each type has its own shortcomings. In this short feature article, we highlight the current advances in the property enhancement of metal hydrides and complex hydrides by incorporating carbon materials, particularly carbon nanostructures such as nanotubes. Carbon with a small curvature radius exhibits prominent "catalytic'' effect in conventional metal hydrides and complex hydrides. The smaller the curvature radius, the stronger the electronic affinity, and the stronger the interaction of carbon with hydrogen, which leads to a change of hydrogen release/combination energy, and consequently improving the de-/rehydrogenation kinetics. Meanwhile, the nanoconfinement effects of carbon scaffolds on all above hydrides were also discussed