Flexible photonic composites with responsive information display based on optical path control

Artificial photonic composites can exhibit the structural colors of embedded colloidal arrays and the functionality of polymeric matrix, making them suitable for emerging applications, such as display, sensing, and information security. However, their ability to integrate flexibility, color visibility and stimulus-responsive macroscopic change has not been adequately harnessed. In this study, a self-supporting photonic composite film is constructed by incorporating isotropically arranged polysulfide nanoparticles (PSNs) into polyethylene glycol diacrylate and butyl acrylate copolymers. The inherent light-absorbing properties and high refractive index of PSNs impart the photonic composites with high structural color visibility. Furthermore, the flexible copolymer network enables sustainable optical capability of photonic pattern during deformation. Due to its unique hydrophobic and hydrophilic structures, tunable optical path control can be achieved through solvent-induced microphase separation and inverse transparency changes under thermal stimulation, resulting in self-encryption and decryption. The function of switching desired stimuli into visualized optical signals allows flexible photonic composites to present great prospects in smart materials for dynamic memory devices.