Molecular dynamics study of lithium intercalation into -OH functionalized carbon nanotube bundle

The influence of hydroxyl group (-OH) on carbon nanotube (CNT) interacting with lithium (Li) ions has been investigated via ab initio molecular dynamic (MD) simulations. Compared with the pure CNT, a higher efficiency has been observed for lithium intercalating into CNT-OH bundle. At lower Li ion density and CNT bundle density, CNT-OH exhibits higher intercalation efficiency than the pristine and ammonium functionalized CNTs. As the increasing of Li ion densities and CNT bundle densities, Li ions tend to intercalate into the interlayer between CNT-OH tubes instead of the interior of CNT-OH tubes. We also observe the destruction of hydroxyl groups during the intercalation of Li ions into interlayer of CNT-OH bundle. It is therefore suggested that eliminating the intercalation of Li ions into interlayer between tubes is important for the design of Li ion batteries.