Polymer-Based p-Type Exciplex Systems for Air-Stable and Processable Organic Persistent Luminescence

We report the first p-type polymer-based multicomponent exciplex system exhibiting persistent luminescence (PersL). Using poly(N-vinylcarbazole) as the polymer donor host, with 2,4,6-tris(4-methoxyphenyl)pyrylium tetrafluoroborate and N,N′-Bis(1-naphthalenyl)-N,N′-bis-phenyl-(1,1′-biphenyl)-4,4′-diamine as the acceptor and trap material, respectively, this system achieves an afterglow lasting over 3 h. It directly addresses the critical drawbacks of existing n-type or small-molecule exciplex systems, namely rapid quenching of their PersL by oxygen and poor processability. Moreover, the developed polymer-based p-type exciplex is readily prepared through a one-pot “boil-up” protocol followed by a brief annealing step, and presents excellent thermal moldability. Through detailed charge carrier dynamics investigations and the study of the effects of various environmental conditions, we uncover new mechanistic insights and their underlying phenomena. This work establishes a robust and process-friendly platform for organic PersL, potentially broadening its applications in anticounterfeiting─as demonstrated here with a multilayer anticounterfeiting QR-code, data encryption, and wearable photonic technologies.