Variation of hydrogen adsorption with increasing Li doping on carbon nanotubes

Abstract

Abstract Density functional theory (DFT) and molecular dynamics (MD) were used to study hydrogen adsorption on the external surface of single‐walled carbon nanotubes decorated with Li. We considered doping ratios of C 64 Li, C 8 Li, and C 4 Li. We found that these systems could store up to 0.77, 3.7, and 7.6 wt.% hydrogen, respectively, at atmospheric pressure and 300 K. The latter case satisfies the requirement for technological applications. However, experimentally, carbon nanotubes are in bundles. Therefore, we studied a bundle of nanotubes each with coverage C 4 Li, under the same conditions. We found that the hydrogen storage capacity is drastically reduced to 2.7 wt.%. This figure is very similar to experimental results.