Hydrogen Storage in Boron Nitride and Carbon Nanomaterials

Abstract

Thermogravimetry/differential thermogravimetric analysis of boron nitride (BN) nanomaterials showed possibility of hydrogen storage of 1–3 wt%. Possibility of hydrogen gas storage in BN and carbon (C) clusters was investigated by molecular orbital calculations. Chemisorption calculation of hydrogen for BN clusters showed that hydrogen bondings with nitrogenatoms and tetragonal rings were the most stable. Conditions of H2 gas storage in B36N36 cluster, which was considered as a cap structure of B99N99 nanotube, were predicted by first principle single point energy calculations. H2 molecules would beintroduced from hexagonal rings of the cage structure. Stability of H2 molecules inside BN and C clusters was alsoinvestigated by molecular orbital calculations. C and BN clusters showed possibility of hydrogen storage of 6.5 and 4.9wt%, respectively. Chemisorption calculation was also carried out for B24N24 with changing endohedral elements in BNcluster to compare the bonding energy at nitrogen and boron, which showed that Li is a suitable element for hydrogenationto B24N24. BN fullerene materials would store H2 molecule easier than carbon fullerene materials, and its stability for hightemperature would be good.