Chiral Self-Assembly of Cellulose Nanocrystals is Driven by Crystallite Bundles
The transfer of chirality across length-scales is an intriguing and universal natural phenomenon. However, connecting the properties of individual building blocks to the emergent features of their resulting large-scale structure remains a challenge. In this work, we investigate the origins of mesophase chirality in cellulose nanocrystal suspensions, whose self-assembly into chiral photonic films has attracted significant interest. By correlating the ensemble behaviour in suspensions and films with a quantitative morphological analysis of the individual nanoparticles, we reveal an inverse relationship between the cholesteric pitch and the abundance of laterally-bound composite particles. These bundles thus act as colloidal chiral dopants, analogous to those used in molecular liquid crystals, providing the missing link in the hierarchical transfer of chirality from the molecular to the colloidal scale.
Funder: Emil Aaltosen Säätiö (Emil Aaltonen Foundation); doi: https://doi.org/10.13039/501100004756
Funder: Philip Leverhulme Prize [PLP-2019-271]; Lord Lewis Research Studentship in Chemistry.
Engineering and Physical Sciences Research Council (1948659)
Engineering and Physical Sciences Research Council (EP/L015978/1)
Engineering and Physical Sciences Research Council (EP/N509620/1)
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (722842)
Engineering and Physical Sciences Research Council (EP/P030467/1)
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (893136)
European Commission Horizon 2020 (H2020) ERC (101001637)