Effect of thermal treatments on chiral nematic cellulose nanocrystal films.

Change log
Guidetti, Giulia 
Frka-Petesic, Bruno  ORCID logo  https://orcid.org/0000-0001-5002-5685
Dumanli, Ahu G 
Hamad, Wadood Y 

The ability to manipulate the optical appearance of materials is essential in virtually all products and areas of technology. Structurally coloured chiral nematic cellulose nanocrystal (CNC) films proved to be an excellent platform to design optical appearance, as their response can be moulded by organising them in hierarchical architectures. Here, we study how thermal treatments influence the optical appearance of structurally coloured CNC films. We demonstrate that the CNCs helicoidal architecture and the chiral optical response can be maintained up to 250 °C after base treatment and cross-linking with glutaraldehyde, while, alternatively, an exposure to vacuum allows for the helicoidal arrangement to be further preserved up to 900 °C, thus producing aromatic chiral carbon. The ability to retain the helicoidal arrangement, and thus the visual appearance, in CNC films up to 250 °C is highly desirable for high temperature colour-based industrial applications and for passive colorimetric heat sensors. Similarly, the production of chiral carbon provides a new type of conductive carbon for electrochemical applications.

Carbonisation, Cellulose nanocrystals, Chiral carbon, Cross-linking, Photonic pigments, Thermal stability, Carbon, Cellulose, Color, Cross-Linking Reagents, Electrochemistry, Glutaral, Hot Temperature, Microscopy, Electron, Scanning, Nanoparticles, Optical Phenomena, Spectroscopy, Fourier Transform Infrared, Thermogravimetry
Journal Title
Carbohydr Polym
Conference Name
Journal ISSN
Volume Title
Elsevier BV
Biotechnology and Biological Sciences Research Council (BB/K014617/1)
Engineering and Physical Sciences Research Council (EP/K503757/1)
EPSRC (1525292)
Engineering and Physical Sciences Research Council (EP/R511675/1)
European Research Council (790518)
European Research Council (639088)
BBSRC [BB/K014617/1], EPSRC [1525292, EP/453 R511675/1, EP/K503757/1], European Research Council [ERC-2014-STG H2020 454 639088, ERC-PoC-2017 790518], BP-ICAM Kathleen Lonsdale Research Fellowship
Is supplemented by: