New alkali doped pillared carbon materials designed to achieve practical reversible hydrogen storage for transportation

We propose a new generation of materials to maximize reversible H-2 storage at room temperature and modest pressures (<20 bars). We test these materials using grand canonical Monte Carlo simulations with a first-principles-derived force field and find that the Li pillared graphene sheet system can take up 6.5 mass% of H-2 (a density of 62.9 kg/m(3) at 20 bars and room temperature. This satisfies the DOE (Department of Energy) target of hydrogen-storage materials for transportation. We also suggest ways to synthesize these systems. In addition we show that Li-doped pillared single-wall nanotubes can lead to a hydrogen-storage capacity of 6.0 mass% and 61.7 kg/m(3) at 50 bars and room temperature storage, which is close to the DOE target.