Preparation of single-handed helical carbon/silica and carbonaceous nanotubes by using 4,4'-biphenylene-bridged polybissilsesquioxane.

Single-handed, helical, 4,4'-biphenylene-bridged polybissilsesquioxane nanotubes were prepared by using the self-assemblies of a pair of chiral low-molecular-weight gelators as templates. Single-handed, helical, carbon/silica nanotubes were obtained after carbonization of the self-assemblies, and single-handed helical carbonaceous nanotubes were then obtained by removal of silica with aqueous HF. Samples were characterized by using field-emission SEM, TEM, X-ray diffraction, thermogravimetric analysis, Raman spectroscopy, and circular dichroism. The polysilsesquioxane and carbonaceous structures exhibited optical activity. The walls of the carbon/silica and carbonaceous nanotubes were predominantly amorphous carbon. The surface area of the left-handed, helical, carbonaceous nanotubes was 1439 m(2) g(-1), and such materials have potential applications as catalyst supports, chirality sensors, supercapacitor electrodes, and adsorbents.