Highly Flexible and Reversible Stimuli-Responsive Photonic Crystal Film in Anti-Counterfeit, Detector, and Coating

Circularly Polarized Luminescence in Cellulose-Based Assemblies: Synthesis, Regulation, and Application

Currently, circularly polarized luminescence (CPL) has drawn wide interest in 3D display, information storage, and optical sensing. However, traditional synthetic paths are often accompanied by low chiral optical intensity and complex processes. Cellulose nanocrystals (CNCs), with the properties of liquid crystals, can spontaneously arrange into the left-handed layered nanofilm, which enables them candidates in the construction of CPL materials. Following this approach, this work reviews the synthesis of cellulose-based chiral luminescent materials. The co-assembly technique, in situ intercalation strategy, and defect destruction design are efficient in encapsulating the luminophores into the CNC organization. Next, various strategies on the CPL regulation, including the matching of the photonic bandgap, optical pathway design, and tailored helical structure, are summarized. These offer new sights in the CPL control, mainly focusing on the amplification and inversion of optical signals. Multimodal and convertible chiroptical signals enable the photonic films with practical values in anti-counterfeit, sensing, and handedness induction. Overall, this timely overview summarizes the synthesis, regulation, and application of cellulose-based CPL materials, and aims to inspire the development of the chiral optical materials.