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arXiv · 0902.2339

Hydrogen Storage by Polylithiated Molecules and Nanostructures

Süleyman Er·Gilles A. de Wijs·Geert Brocks
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Abstract

We study polylithiated molecules as building blocks for hydrogen storage materials, using first-principles calculations. $\clifour$ and $\olitwo$ bind 12 and 10 hydrogen molecules, respectively, with an average binding energy of 0.10 and 0.13 eV, leading to gravimetric densities of 37.8 and 40.3 weight % H. Bonding between Li and C or O is strongly polar and $\hyd$ molecules attach to the partially charged Li atoms without dissociating, which is favorable for (de)hydrogenation kinetics. CLi$_n$ and OLi$_m$ molecules can be chemically bonded to graphene sheets to hinder the aggregation of such molecules. In particular B or Be doped graphene strongly bind the molecules without seriously affecting the hydrogen binding energy. It still leads to a hydrogen storage capacity in the range 5-8.5 wt % H.

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Süleyman Er, Gilles A. de Wijs, Geert Brocks. 2009-02-13. Hydrogen Storage by Polylithiated Molecules and Nanostructures. https://doi.org/10.1021/jp901305h

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