Chiral self-assembly of cellulose nanocrystals is driven by crystallite bundles

• DOI: 10.1038/s41467-022-30226-6
• Publication Date: 2022-05-12T10:33:06Z
• Authors: Thomas G. Parton; Richard M. Parker; Gea T. van de Ker...; Aurimas Narkevicius; Johannes S. Haataja; Bruno Frka-Petesic; Silvia Vignolini
• Keywords: /639/301/54/989; /147/135; Optics and Photonics; /147/3; /123; Science; FOS: Physical sciences; 02 engineering and technology; Condensed Matter - Soft Condensed Matter; 01 natural sciences; Article; /639/301/923/966; /639/624/399/1022; Suspensions; /128; Cellulose; Q; /639/301/923/919; article; /639/301/923/916; Liquid Crystals; 0104 chemical sciences; Soft Condensed Matter (cond-mat.soft); Nanoparticles; 0210 nano-technology; /147/143

AbstractThe 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.