CINCOS · Chirality inversion in colloidal self-assembly
Horizon Europe — Marie Skłodowska-Curie Actions
- Duration
- 2024-05-01 → 2026-04-30
- EU contribution
- €173,847
- Participants
- 2
- Scheme
- HORIZON-TMA-MSCA-PF-EF
Lines connect the coordinator with its partners.
Results in brief
Chirality inversion in colloidal self-assembly
Structurally-coloured films made from cellulose, the world’s most abundant biopolymer, show great promise as a sustainable alternative to conventional effect pigments and glitter. This colouration arises from the colloidal self-assembly of rod-like cellulose nanocrystals (CNCs), which spontaneously form a cholesteric liquid crystal phase with a helical periodic structure. In this system, control over colloidal chirality is crucial, because the handedness of the self-assembled structure determines the optical response and thus the colour and polarisation properties of the resulting films. Although cellulose can form both left- and right-handed helicoidal structures in nature, naturally-derived colloidal cellulose only forms a left-handed cholesteric phase, limiting the optical performance of CNC-based colourants. The CINCOS fellowship therefore explored how the morphology of CNCs could be tuned to control their self-assembly and enable structurally coloured films with inverted chirality, opening a route to more efficient and sustainable photonic materials for colours, pigments, and glitter replacements.
Data: CORDIS, © European Union
Project objective
The chiral self-assembly of nanoscale building blocks offers a scalable route to functional materials, but understanding and controlling this process is a persistent challenge. A notable example is cellulose nanocrystals (CNCs), elongated nanoparticles extracted from natural cellulose that assemble into a cholesteric liquid crystal phase in aqueous suspension. This helicoidal self-organisation can be preserved into the solid state to create structurally coloured films, offering a sustainable way to produce next-generation pigments and colourants. However, the CNC cholesteric phase is always found to be left-handed due to the presence of ""bundles"", a sub-population of CNCs that act as colloidal chiral dopants and induce left-handed ordering. Inspired by the naturally-occuring CNC bundles, this project aims to produce cellulose polycrystals (CPCs), a new class of clustered nanoparticles produced by the aggregation of CNCs in the presence of a chiral ""glue"" provided by hemicelluloses. These CPCs will then be used as synthetic chiral dopants to induce a right-handed cholesteric phase in CNCs suspensions for the first time. This inversion of the handedness of CNC self-assembly will result in films that reflect RCP light in the visible range, enabling the creation of structurally-coloured materials with near-ideal optical performance. These findings will deepen our understanding of chiral colloidal self-assembly and open up new avenues of enquiry for research on bio-sourced nanomaterials.""
Original text from CORDIS.
Participants
- MAX-PLANCK-GESELLSCHAFT ZUR FORDERUNG DER WISSENSCHAFTEN EV · MUNCHENCoordinatorGermany
- REGENTS OF THE UNIVERSITY OF MICHIGAN · ANN ARBORUnited States
Links
- View on CORDIS
- DOI: 10.3030/101154876
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e516e59a0e&appId=PPGMS
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e52c5fff34&appId=PPGMS
Data: CORDIS, © European Union