Chemisorption of Hydrogen on the Armchair Boron-Nitride Nanotubes:A Density Functional Study

Nowadays, it is known that nanotubes can be use as one class of candidate materials for the effective storage of hydrogen, a green source for energy. Hence, many experimental and theoretical groups have been investigated the process of hydrogen adsorption on the nanotube medium [1]. Hydrogen can interact with nanotube via two different mechanisms: physisorption (molecular adsorption) and chemisorption (atomic adsorption). Recently, Leszczynski et al. [2] reported the chemisorption of one and two hydrogen atoms on the external surface of armchair single-walled carbon nanotubes (SWCNTs). A boron nitride nanotube (BNNT) is a structural analogue of a carbon nanotube (CNT) in nature alternating B and N atoms entirely substitute for C atoms in a graphiticlike sheet with almost no change in atomic spacing. BNNTs were theoretically predicted [3, 4] and then successfully synthesized in 1995. Ma et al.[5] found experimentally that BNNTs may be used to store hydrogen and about 70% of adsorbed hydrogen is chemisorbed.