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Three chiral cationic gelators were synthesized. They can form translucent hydrogels in pure water. These hydrogels become highly viscous liquids under strong stirring. Mesoporous silica nanotubes with coiled pore channels in the walls were prepared using the self-assemblies of these gelators as templates. The mechanism of the formation of this hierarchical nanostructure was studied using transmission electron microscopy at different reaction times. The results indicated that there are some interactions between the silica source and the gelator. The morphologies of the self-assemblies of gelators changed gradually during the sol-gel transcription process. It seems that the silica source directed the organic self-assemblies into helical nanostructures.

An anionic gelator, D-C12ValC10COONa, derived from D-valine can cause physical gels in water and organic solvents. Helical 4,4(')-biphenylene-silica nanotubes and nanoribbons were prepared using it with 3-aminopropyltrimethoxysilane as a co-structure-directing agent and 4,4(')-bis(triethoxysilyl)-1,1(')-biphenyl (BTESB) as precursor. It was found that the handedness of the hybrid silica nanotubes/nanoribbons is sensitive to the pH value and the concentration of the reaction mixtures. However, handedness inversion was not found by changing the reaction temperature. Circular dichroism spectra of the 4,4(')-biphenylene-silica nanotubes indicated that the chirality of the organic self-assemblies were successfully transferred to the twist of the biphenylene rings through the co-structure-directing agent. The handedness of the 4,4(')-biphenylene rings was also tunable by changing the pH value and the concentration of the reaction mixtures. The FESEM images and CD spectra taken after different reaction times indicated that the handedness inversion occurred after adding BTESB.

A chiral low-molecular-weight amphiphile, L- 18Ala11PyPF(6), was synthesized from L-alanine. Hollow silica nanoworms with circular pore channels parallel to the shell surfaces and holes at the terminals were prepared using the self-assemblies of it as templates via a single-templating approach. The formation of this hierarchical structure was studied by taking TEM images after different reaction time and changing reaction conditions. It was found that the morphologies of the amphiphile-silica assemblies changed gradually during the sol-gel transcription process.

A new chiral cationic amphiphile has been synthesized. Sol-gel transcriptions were carried out to control mesoporous silica nanostructures using the organic self-assemblies of this amphiphile as templates. Left-handed coiled mesoporous silica nanoribbons were obtained in the mixture of 1-propanol and 2.5 wt% NH(3) aq. at the ratio of 2:8 and 0 °C. However, right-handed coiled mesoporous silica nanoribbons were prepared in 2.5 wt% NH(3) aq. at 25 °C. The organization of the low-molecular-weight gelators plays an important role in this handedness inversion.