A Chiral Cocrystal Strategy Producing Room‐Temperature Phosphorescence and Enhancing Circularly Polarized Luminescence

Abstract

The maintenance of triplet excitons to produce room‐temperature phosphorescence while simultaneously improving the luminescence dissymmetry factor (glum) and photoluminescence quantum yield (PLQY) makes the preparation of circularly polarized room‐temperature phosphorescence (CP‐RTP) materials challenging. Herein, two chiral cocrystals are reported with CP‐RTP using S/R‐1‐(1‐Naphthyl)ethanol (S/R‐1‐nea) as the donor and 1,2,4,5‐Tetracyanobenzene (TCNB) as the acceptor. Simultaneous enhancement of glum and PLQY is accomplished, with the greatest phosphorescence in the PLQY of ≈31% and |glum| of 0.065, which is one of the highest |glum| in cocrystals. Doping two chiral cocrystals into the polyvinyl alcohol (PVA) matrix resulted in polymer films with circularly polarized long afterglow luminescence, indicating the potential for multilevel encryption applications. This study provides a novel approach to achieve the dual improvement of glum and phosphorescence PLQY, and broadens the application prospects of CP‐RTP materials.