ausblenden:
Schlagwörter:
cellulose
cellulose nanocrystal
nanomaterial
pigment
solvent
nanoparticle
dispersion
Article
color
geometry
optical spectroscopy
photonics
pitch
polarimetry
scanning electron microscopy
suspension
thermogravimetry
transmission electron microscopy
chemistry
optics
photon
Nanoparticles
Nanostructures
Optics and Photonics
Photons
Zusammenfassung:
When pursuing sustainable approaches to fabricate photonic structures, nature can be used as a source of inspiration for both the nanoarchitecture and the constituent materials. Although several biomaterials have been promised as suitable candidates for photonic materials and pigments, their fabrication processes have been limited to the small to medium-scale production of films. Here, by employing a substrate-free process, structurally coloured microparticles are produced via the confined self-assembly of a cholesteric cellulose nanocrystal (CNC) suspension within emulsified microdroplets. Upon drying, the droplets undergo multiple buckling events, which allow for greater contraction of the nanostructure than predicted for a spherical geometry. This buckling, combined with a solvent or thermal post-treatment, enables the production of dispersions of vibrant red, green, and blue cellulose photonic pigments. The hierarchical structure of these pigments enables the deposition of coatings with angular independent colour, offering a consistent visual appearance across a wide range of viewing angles. © 2022, The Author(s).
