Plugging and unplugging holes of single-wall carbon nanohorns

We demonstrate that gadolinium acetate could plug holes of single-wall carbon nanohorns (NHox) and that unplugging was also possible. A quantitative evaluation of the plugging and unplugging using C-60 as a probe showed that about 50% of NHox were hole-plugged with gadolinium acetates and most of them were unplugged with water. The plugging and unplugging will enhance new uses of NHox and other carbon nanotubes for storing, carrying, and supplying material.