Computational studies on hydrogen storage in aluminum nitride nanowires/tubes.

One-dimensional AlN nanowires/tubes were exploited as hydrogen storage media. The adsorption of atomic and molecular hydrogen on AlN nanowires was investigated by using density functional theory computations. Hydrogen atoms prefer to adsorb on top of neighboring threefold-coordinated N and Al atoms in pairs. A hydrogen molecule, however, prefers to adsorb on top of threefold-coordinated Al atoms in the nanowire surface, with an adsorption energy of 0.21 eV. H(2) dissociation is exothermic in the surface of AlN nanowires, and the dissociation barrier is rather low (0.76 eV), indicating that chemisorption is a feasible route for hydrogen storage in AlN nanowires/tubes. A maximum 3.66 wt% of molecular and 2.44 wt% of atomic hydrogen can be stored in AlN nanowires/tubes.