Published online by Cambridge University Press: 10 February 2011
We performed density-functional calculations to search for adsorption sites and predict maximum hydrogen storage capacity in carbon nanotubes. Our calculations show that the storage capacity of hydrogen, limited by the repulsive forces between H2 molecules inside nanotubes, increases linearly with tube diameters in single-walled nanotubes, whereas this value is independent of tube diameters in multi-walled nanotubes. We predict that H storage capacity in (10,10) nanotubes can exceed 14 wt % (161 kg H2/m3).