Room-Temperature Phosphorescence Induced by Heterogeneous Polymer Matrixes

Room-temperature phosphorescence (RTP) materials based on phosphor-doped polymers have been studied for more than 60 years. In these polymer-based RTP materials, the intrinsic structures and properties of polymeric matrixes are critical to their triplet emission. However, RTP materials with heterogeneous matrixes are rarely studied, and far too little attention has been paid to the possible interferences of structures and components of polymeric matrixes on the final photophysical properties. In this work, we reported RTP materials with phase-separated matrixes consisting two incompatible polymers, i.e., polystyrene (PS) and polyisoprene (PI). While no afterglow can be observed in difluoroboron β-diketonate derivative (D1)-doped PS nor PI homopolymers, bright and long-lived green RTP emission with duration >6 s can be obtained in D1-doped heterogeneous matrixes consisting of PS and PI. We investigated the mechanism of RTP emissions in the heterogeneous matrixes and demonstrated the synergy of incompatible polymers on the stabilization of triplet excitons. The findings of this work add substantially to our understanding on the emission mechanism of polymer-based RTP materials and provides a new approach to the low-cost fabrication of RTP materials through high-throughput processing methods.