Chiral Nematic Stained\nGlass: Controlling the Optical\nProperties of Nanocrystalline Cellulose-Templated Materials

Abstract

Chiral nematic mesoporous materials decorated with metal\nnanoparticles\nhave been prepared using the templated self-assembly of nanocrystalline\ncellulose (NCC). By adding small quantities of ionic compounds to\naqueous dispersions of NCC and tetramethoxysilane (TMOS), the helical\npitch of the chiral nematic structure could be manipulated in a manner\ncomplementary to the ratio of NCC/TMOS previously demonstrated by\nour group. We have studied the transformation of these ion-loaded\ncomposites into high surface area mesoporous silica and carbon films\ndecorated with metal nanoparticles through calcination and carbonization,\nrespectively. This general and straightforward approach to prepare\nchiral nematic metal nanoparticle assemblies may be useful in a variety\nof applications, particularly for their chiral optical properties.