Self‐Assembled Heterosymmetric Structure with Tunable Polarization Optics for Reversible Matrix Encryption
Qun Song, Xintong Meng, Caoxing Huang, Mingcong Xu, Tao Chen, Ziwei Zhou, Philipp Vana, Kai Zhang
Abstract
Abstract Symmetric and asymmetric structures are generally taken as contradictory structures. Developing novel hierarchical self‐assembled structures by harmonically combining both symmetry and asymmetry, which we termed “heterosymmetric structures”, along with quantitative analysis of their formation process, remains underexplored but is crucial for advancing science and applications. Herein, we create novel heterosymmetric architectures using sustainable colloidal nanoparticles, cellulose nanocrystals (CNC), and hydrophilic nanolignin (NL), by modulating their evaporation kinetics and deposition behaviors to fabricate heterosymmetric films with tunable polarized optical properties for time‐dependent reversible matrix encryption. During drying, the increased concentration within CNC/NL colloidal droplets and the liquid crystal phase separation induced by CNC regulate the dynamic competition between Marangoni and capillary flows. Erickson number quantifies the influence of liquid crystal elasticity and viscous forces at the triple‐phase contact line in heterosymmetric structure formation. The unique heterosymmetric nature of the resulting films imparts a cross‐extinction pattern accompanied by strong birefringence, circular dichroism, circularly polarized luminescence with high luminescence asymmetry factor up to 0.6 and dynamic solvent responsiveness, enabling successful multilevel encryption applications. The insights in this study not only expand the knowledge of symmetric/asymmetric structures but also enhance understanding of collective behaviors in non‐equilibrium systems for self‐assembling various hierarchical structures with promising properties.