Hydrogenation of substituted fullerenes - A DFT study

Abstract

Hydrogen storage by carbon materials is a topic of current interest. In order to exploit fullerenes one of the new forms of carbon for hydrogen storage, it is shown that an activator for hydrogen is necessary in the fullerene network. Even though one can generate stoichiometric hydrides the formation of such hydrides have to be established. In this present study we have examined what type of species on carbon surfaces may be able to activate hydrogen molecule and lead to hydride formation. The density functional calculations have been carried out on some typical model systems wherein the fullerene molecule is substituted in the network with hetero-atoms like N, P and S and the reduction in the dissociation energy of hydrogen molecule is considered as a measure of the ability to hydride the carbon materials. On the basis of the reduction in the dissociation energy for the hydrogen molecule it has shown that hetero atom substitution in the fullerene net work may be suitable for the activation and dissociation of hydrogen molecule.