Chiroptical Cellulose Nanocrystal-Based Circularly Polarized Reflector and Filter for the Chiral Regulation of Photoresponsive Supramolecular Polymers

The regulation of circularly polarized light (CPL) is crucial to many photonic applications such as stereoscopic displays and asymmetric synthesis. Here, chiroptical cellulose nanocrystal (CNC) film-based circularly polarized reflectors and filters are demonstrated. CPL with high dissymmetry factors and opposite handedness can be achieved using these CNC-based chiroptical devices, and they are used to induce and regulate the helical structures of achiral azobenzene supramolecular polymers. The induced chirality of azobenzene supramolecular polymers depends on the handedness of CPL. In addition, chiral structures of azobenzene polymers can be switched reversibly by changing the Reflected-CPL and the Transmitted-CPL. What is more is that the photoinduction strategy can be successfully applied to azobenzene polymers with different tail groups. This work paves the way for exploiting efficient CPL devices from biomass materials.