A single tiny Tin(O2)n cluster decorated an ultra-small boron nitride nanotube for hydrogen storage material: A density functional theory study

The adsorption of hydrogen (H2) on tiny titanium dioxide Tin(O2)n clusters where n = 1, 2 and 3 decorated a (5, 5) ultra-small boron nitride nanotube (BNNT) is studied theoretically using the density functional theory calculation. Tin(O2)n/BNNT is very stable and it can hold a large number of H2 molecules while maintaining its stability. That H2 adsorption on Tin(O2)n/BNNT/BNNT shifts the geometry of Tin(O2)n/BNNT as the number of H2 molecules adsorbed on its surface increased. For example, the bond between N–O increases while the bond between the H atoms in the H2 molecules shortens. Furthermore, the local density of states (LDOS), crystal orbital overlaps population (COOP), and charge distribution analysis all confirm that H2 formed a bond with TiO2/BNNT. Thus, we can conclude that Tin(O2)n/BNNT is a promising material for hydrogen storage.