Molecular hydrogen storage in Al-doped bulk graphite with wider layer distances

Molecular hydrogen storage at room temperature in At-doped bulk graphite with wider layer distances was studied using density functional theory calculation. Hydrogen storage capacity of 3.48 wt% or volume density of 51 kg/m(3) was predicted at T = 300 K and P = 0.1 GPa with adsorption energy E-b = -0.264 eV/H-2. This is close to the target of volume density 62 kg/m(3) and satisfies the requirement of immobilization hydrogen with binding strength of 0.2-0.7 eV/H-2 at ambient temperature and modest pressure for commercial applications specified by the U.S. Department of Energy. (C) 2009 Elsevier Ltd. All rights reserved.