High Performance Full-Color Room-Temperature Phosphorescence Polymer Microspheres and Their Applications

Room temperature phosphorescence (RTP) polymer materials, known for their unique modifiability and ease of preparation, hold broad potential for applications in flexible electronics and information encryption. However, polymers make their RTP properties with high quantum yields (Φ_P) but short phosphorescence lifetimes (τ_P), or long τ_P but low Φ_P due to their flexible structure. Herein, we propose a novel in situ cross-linked self-assembly strategy of flexible weak RTP polymers into rigid polymer microspheres with long τ_P, high Φ_P and high brightness. The maximum τ_P and Φ_P of the RTP microsphere (PM1) reach as high as 2020 ms and 34.1%, with the phosphorescence brightness as high as 655.1 mcd/m², which are 6.4-, 5.3-, and 10.2-fold higher than those of its flexible intrinsic polymer (P1), respectively, and also considerably superior to those of the previously intrinsic polymer RTP materials. Moreover, the cross-linked polymer microspheres exhibit excellent stability in strong acids and bases, and even after 30 days in water. The RTP microsphere-doped polymer film (PM1-PVA) presents highly selective recognition of aniline and a detection sensitivity as low as 3.7 × 10^{- 8} m.