Hierarchical Assembly of Patternable Chiroptical Biotextiles with Extreme Environment Stability

Flexible photonic textiles constructed by sustainable cholesteric organization are very promising to achieve a combination of chiroptical structural colors, mechanical robustness, sustainability, and environment stability. However, the efficient assembly of well-ordered cholesteric nanoarchitectures on flexible textiles in a scalable and patternable manner remains a grand challenge. In this study, we develop an efficient and scalable approach to construct large area chiroptical biotextiles using renewable and bioenabled cellulose nanocrystals (CNCs) as building blocks. This hierarchical assembly enables cholesteric photonic CNCs "cast" in situ, in a seamlessly tessellated design, onto topography-tailored textiles to form a strong interlocked multilayered structure. The resulting hierarchical architecture not only comprises strong photonic-photonic coupling to synergistically enhance the chiroptical properties with tunable wavelengths but also leads to impressive mechanical and optical stability against external mechanical forces and extreme environments. More importantly, through regulating the localized photonic band of the preformed chiroptical textiles by small molecules (e.g., water and glucose), customized colored patterns can be easily generated in large scale that are highly responsive to multistimuli, including chiral polarized light, view angle, and solvent. This chiroptical biotextile is a promising next-generation biomimetic photonic material for defense, aviation, and marine and aerospace special applications.