Convenient large-area construction of flexible multicolor polymer-based room temperature phosphorescence materials with second-scale phosphorescence lifetimes

Abstract

The preparation of multicolor organic room temperature phosphorescence (RTP) materials with flexibility and second-scale phosphorescence lifetime is highly attractive yet remains extremely challenging. Here, we synthesize a series of carbazole-functionalized polyacrylamide copolymers P(AM-co-VBC) by free radical copolymerization, which can show up to 20 s of a bright blue afterglow accompanied by 3.720 s of the RTP lifetime. After water-dissolution and drying treatments, the bright blue afterglow of W-P(AM-co-VBC) visible to the naked eye is extended to 43 s, while the longest RTP lifetime increases to 4.664 s due to the self-assembly of carbazole group aggregates inducing an aggregation-induced emission enhancement effect. Using W-P(AM-co-VBC) as an energy donor and commercially available fluorescent dyes as energy acceptors, multicolor RTP materials are facilely prepared through a phosphorescence Förster resonance energy transfer strategy. Notably, flexible multicolor RTP films with high transparency and long RTP lifetime are conveniently fabricated over large areas by doping the multicolor RTP materials into sodium alginate matrices with trace amounts of poly(vinyl alcohol) as a regulator. Furthermore, the prepared multicolor ultralong RTP materials demonstrate significant potential for advanced applications in the fields of information encryption and flexible display.