Color-Tunable Circularly Polarized Room-Temperature Phosphorescence by Intermolecular Phosphorescence Resonance Energy Transfer in a Chiral Co-assembled Liquid Crystal Polymer Network

Circularly polarized room-temperature phosphorescent (CP-RTP) materials have been attracting great attention due to their potential applications in anticounterfeiting. In this study, we designed and synthesized a host–guest copolymer ( PBXT ) with strong phosphorescence emission and a long emission lifetime using a self-doping strategy. The co-assembled liquid crystal polymer networks (LCPNs) x –( R I / S I ) y doped with PBXT demonstrated a stronger RTP emission and longer lifetime (τ = 148 ms). Among them, (LCPNs) 0.91 –( R I ) 0.09 showed strong CP-RTP signals (| g RTP | = 0.071) through chiral supramolecular co-assembly. By dropping Nile Red ( NR ) into (LCPNs) 0.91 –( R I / S I ) 0.09, the resulting [(LCPNs) 0.91 –( R I / S I ) 0.09 ] 0.9925 –(NR) 0.0075 emitted intense red circularly polarized luminescence (CPL) of NR dye (λ em = 636 nm and | g em | = 0.073) with a long lifetime (τ = 26 ms) under the regulation of an intermolecular phosphorescence resonance energy transfer (PRET) mechanism. Additionally, [(LCPNs) x –( R I / S I ) y ] m –(NR) n has been explored for applications in time-varying information encryption and quadruplex anticounterfeiting information encryption through the PRET progress.