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Left-handed,coiled,4,4’-biphenylene bridged polybissilsesquioxane,tubular nanoribbons were prepared according to the published literature.After carbonization and removal of silica using HF aqueous solution,left-handed,coiled,carbonaceous,tubular nanoribbons were obtained.The lefthanded,coiled,carbonaceous,tubular nanoribbons were characterized using field-emission scanning electron microscopy,transmission electron microscopy,powder X-ray diffraction,Raman spectrophotometer,diffuse reflectance circular dichroism(DRCD),and N_2 adsorptions.Micropores were formed due to the removal of silica.The nitrogen BET surface area is 1727 m~2/g.A broad,positive DRCD signal,identified at 400-800 nm,indicates the carbonaceous,tubular nanoribbons exhibit optical activity.The helical pitch is proposed to play an important role in the position of the DRCD signal.
Left-handed, coiled, 4,4’-biphenylene bridged polybissilsesquioxane, tubular nanoribbons were prepared according to the published literature. After carbonization and removal of silica using HF aqueous solution, left-handed, coiled, carbonaceous, tubular nanoribbons were obtained. lefthanded, coiled, carbonaceous, tubular nanoribbons were characterized using field-emission scanning electron microscopy, transmission electron microscopy, powder X-ray diffraction, Raman spectrophotometer, diffuse reflectance circular dichroism (DRCD), and N_2adsorptions. Micropores were formed due to the removal of silica. The silica BET surface area is 1727 m ~ 2 / gA broad, positive DRCD signal, identified at 400-800 nm, indicating the carbonaceous, tubular nanoribbons exhibit optical activity. The helical pitch is proposed to play an important role in the position of the DRCD signal.