Characterization of single wall carbon nanotubes by nonane preadsorption

The preferential blocking of the interior adsorption sites of single walled carbon nanotubes (SWNTs) by n-nonane is demonstrated. Following adsorption of n-nonane and evacuation for 24 h at 323 K, it was found that interior sites with diameters less than ∼14 Å remained filled with n-nonane, blocking the physical adsorption of N₂ on these sites at 77.3 K. We demonstrate that “nonane blocking” is a very useful technique for nanotube porosity characterization.