Aiegen-based fluorescent polymer films with tunable Janus luminescence and structural color

Fluorescent polymer films (FPFs) doped with aggregation-induced emission luminogens (AIEgens) have attracted great attention of scientists for their potential to solve the aggregation-caused quenching effect of traditional fluorescent molecules. Here, to rich the information and enhance the function of FPFs, AIEgens (DCDPP-2TPA) doped FPF was placed in the middle of two different inverse opal photonic crystals (IOPCs), whose photonic band gaps matched with the FPF's red and blue region respectively. Owing to the regulation effect of the IOPCs, tunable Janus luminescence and structural color depending on the viewing angle were achieved. Through designing complex patterns in FPFs, encrypted information can be decoded simply by ultraviolet light. More importantly, the decoded information displays different luminescent colors on each side, and the luminescence on each side is tunable with viewing angles. The "sandwich" structure can be used in most daily environments. Its unique property of variable Janus emissions and structural colors endow the structure with highly safe anticounterfeiting performance.