Hydrogen chemisorption on carbon structure with mixed sp2–sp3 hybridization: empirical potential studies

Abstract

Hydrogen storage is a key technology for the advancement of hydrogen and fuel cell power technologies in transportation, stationary, and portable applications. The currents state of art shows that there is no existing material which could be used as efficient storage medium. In this paper we present a new concept of a non-conventional engineering storage solution. It is based on the recent theoretical and experimental discoveries which show existence of a new meta-stable phase of graphite with mixed sp2–sp3 hybridization called diaphite. By means of the molecular dynamics calculations with adaptive intermolecular reactive empirical bond order potential empirical potential we show that the increase of the hydrogen-carbon binding energy on diaphite is related to the transformation of local bonds geometry from sp2 hybridization to sp3. We propose and discuss a scenario of fully reversible photo-stimulated process of adsorption/desorption of hydrogen on/of diaphite.