Circularly Polarized Organic Long-Persistent Luminescence from Polymer Films Doped with Chiral Cu(I) Complexes

Abstract

The development of polymer materials with circularly polarized organic long-persistent luminescence (CP-OLPL) remains challenging yet highly desirable. Herein, a polymer-based OLPL system is prepared by embedding a Cu(I) complex rac-NDP-CuCl into polymethyl methacrylate, which exhibits a high phosphorescence quantum yield (Φphos.) of 64.0% and an emission duration exceeding 3 h under ambient conditions. Moreover, by simply replacing the racemic guest rac-NDP-CuCl with its enantiomers R-NDP-CuCl and S-NDP-CuCl, polymer-based luminescent materials with CP-OLPL properties are successfully developed for the first time. These doped polymer films display Φphos. values and emission durations comparable to those of the racemic system, along with satisfactory asymmetry factors for both circularly polarized phosphorescence and OLPL, reaching up to 4.79 × 10−3 at room temperature. In contrast to conventional OLPL systems based on binary donor–acceptor doping, the present design facilitates the formation of intermediate charge-separated states via photoinduced metal-to-ligand charge transfer, which are effectively stabilized and spatially separated within the polar polymer matrix, thereby enabling notable OLPL and CP-OLPL emissions. These findings provide new insights into the molecular design of ambient OLPL materials and open a promising avenue for developing polymer-based CP-OLPL systems.