|Title||Pressure-Responsive Hierarchical Chiral Photonic Aerogels|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Cao, Y, Lewis, L, Hamad, WY, MacLachlan, MJ|
|Type of Article||Article|
|Keywords||chiral 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.