Designs of fullerene-based frameworks for hydrogen storage

Two types of hybrid metallofullerene framework are theoretically designed, and their structural stabilities are examined using the density functional theory (DFT) computation. Both frameworks are constructed by connecting exohedral metallofullerene nodes with conjugated organic linkers, akin to the common metal-organic framework (MOF). The DFT calculations suggest that hydrogen molecules can be adsorbed in the frameworks with the hydrogen binding energies ranging from 0.15-0.50 eV, satisfying the optimal adsorption condition for hydrogen storage. Moreover, our computation suggests that the frameworks can entail molecular H-2 binding in the range of 8.0-9.2 wt%, meeting the Department of Energy (DOE) target of 2010 or 2015.