New Alkali Doped Pillared Carbon Materials Designed to Achieve Practical Reversible Hydrogen Storage for Transportation

Abstract

We propose a new generation of materials to maximize reversible ${\mathrm{H}}_2$ storage at room temperature and modest pressures ($<20\mathrm{bars}$). 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 ${\mathrm{H}}_2$ (a density of $62.9\mathrm{kg}/{\mathrm{m}}^3$ 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 $61.7\mathrm{kg}/{\mathrm{m}}^3$ at 50 bars and room temperature storage, which is close to the DOE target.