Visible-light-controlled ternary chiroptical switches with high-performance circularly polarized luminescence for advanced optical information storage and anti-counterfeiting materials

Photoswitching chiroptical materials with alternate emission colors are urgently demanded due to their promising prospects in the next-generation intelligent materials. Herein, we developed an integrated strategy to design the ternary chiroptical switches through the introduction of phosphorescent platinum(II) and photochromic spiropyran as triplet-sensitizer and photo-regulator building-blocks, respectively, which were bridged by the chiral gene, diaminocyclohexane. This novel tactic synergistically realized the photo-controllable characteristics of triplet-sensitized photochromism, and intramolecular energy and chirality transfer processes regulated by all-visible light. Especially, the phototriggered chirality transformation was effectively achieved from diaminocyclohexane to the open merocyanine moiety via Pt(II) sensitized center, associated with gradually emission color changes from green to red as a result of triplet-singlet exciton transfer from the cyclometalated ligand to the merocyanine moiety. Thereby, the established photo-controlled CPL switches were demonstrated to develop quaternary molecular logic gate, all-visible-light photorewritable patterning and anti-counterfeiting applications with advantage of unique visible-light photochromism including high-performance photostability and robust photo-fatigue resistance.