Enhanced Hydrogen Storage on Li Functionalized BC3 Nanotube

First principles calculations based on density functional theory are carried out to study the effect of lithium functionalization of experimentally synthesized BC3 nanotube on charge transfer, electrostatic potential, and hydrogen storage. Electron-deficient BC3 nanotube is found to promote charge transfer from Li to the substrate when lithiated. The resulting Li ions on the tube surface can effectively polarize hydrogen molecules and improve their binding energy and storage capacity. While each Li site on BC3 nanotube is found to adsorb up to two H-2 molecules, zigzag nanotube shows better performance as a hydrogen storage material with good adsorption energy (0.11 eV/H-2) and high gravimetric density (6.9%). These data are consistent with the system target set by the DOE for 2010.