Research & Teaching Faculty

Pressure-Responsive Hierarchical Chiral Photonic Aerogels

TitlePressure-Responsive Hierarchical Chiral Photonic Aerogels
Publication TypeJournal Article
Year of Publication2019
AuthorsCao, Y, Lewis, L, Hamad, WY, MacLachlan, MJ
Date PublishedMAY
Type of ArticleArticle
Keywordschiral nematic liquid crystals, hierarchical chiral cellulose aerogels, ice templating, mechanoresponsive photonic crystal aerogels, solvent-sensitive inks

Pressure-responsive chiral photonic aerogels are fabricated by combining liquid crystal self-assembly and ice-templating processes. The aerogels have a hierarchical structure in which the primary 2D chiral nematic structured walls of cellulose nanocrystals form ribbons that support a secondary 3D cellular network. Owing to the flexibility of the aerogels in solvent, the 3D structure of the aerogel can easily be transformed to a 2D structure by pressure-induced rearrangement. The aerogels vary from white in color, which arises from light scattering, to a reflective photonic crystal displaying bright iridescent colors that depend on the immersed solvent. A solvent-sensitive ink that shows quick color response to different solvents is designed using the pressure-responsive photonic aerogel. This material demonstrates a new response mechanism for the design of smart and mechanoresponsive photonic materials.