A chirality indicator for the surfaces of the silica nanotubes

J Nanosci Nanotechnol. 2013 Aug;13(8):5732-5. doi: 10.1166/jnn.2013.7553.

Abstract

The chirality of the silicas attracted much attention, due to their potential applications in asymmetric catalysis and enantioseparation. However, their chirality has not been well understood. Herein, a chirality indicator for the surfaces of the silica nanotubes was developed. The helical silica nanotubes were prepared through a sol-gel transcription approach. The handedness was controlled by that of the self-assemblies of the low-molecular-weight amphiphiles. 4-Triethoxysilyl-1,1'-biphenyl (TSB) was modified on the surfaces of silica nanotubes through covalent bonds. The circular dichroism (CD) spectra of the TSB-modified silica nanotubes indicated that the chirality of silica surfaces could be transferred to the twist of the biphenyl rings. The origin of these CD signals was characterized using time-dependent density functional theory.

Publication types

  • Research Support, Non-U.S. Gov't