Photostimuli-Responsive\nTerbium Metallopolymers for\nDynamic Dual-Level Information Encryption

Despite\nremarkable progress regarding anticounterfeiting materials\nthat have been developed recently, integrating multifunctionality\ninto these materials remains a significant challenge. Here, we present\na family of smart light-controlled fluorescence metallopolymers with\nself-healing capabilities based on terbium-bipyridine complexes, spiropyran\n(SP), and a polymer matrix. We achieved light-controlled photoluminescence\ntransformation (including nonluminescent, red, yellow, and blue),\nand the visual color changes from transparent and colorless to purple\nby manually controlling the photoisomerization of SP together with\nexploiting fluorescence resonance energy transfer. Remarkably, the\nlight stimulus response behavior of the materials exhibits significant\ncyclicity. The well-designed polymer matrix endows the material with\nprocessing performance, strong and resilient characteristics (toughness:\n42.73 MJ m<sup>–3</sup>), and fast self-healing ability at\nroom temperature. We have demonstrated the enormous potential of these\nmaterials in dual-level information encryption technologies through\nour research. It is our conviction that the universal approach adopted\nin this study provides invaluable insights and is paving the way for\nthe construction of multifunctional, light-sensitive, smart metallopolymers.