Scalable fabrication of red Room-Temperature phosphorescent materials through molecular doping strategy for versatile applications

Room-temperature phosphorescence (RTP) materials renowned for their long emission lifetime have garnered tremendous research interest not only for elucidating their underlying mechanisms but also for exploring their potential applications in anti-counterfeiting, encryption, and bioimaging. Nevertheless, the RTP color of most organic materials has been limited to blue, green, and yellow. In this study, a series of red RTP materials have been successfully fabricated at a large scale through a straightforward molecular doping strategy. Remarkably, the doped materials exhibited red RTP at 622 nm and 678 nm with an ultralong lifetime of 373 ms and an efficiency of 5.21 %, which was among the best performances reported for organic RTP materials. The systematic investigation unveiled that the efficient RTP emanated from the robust interactions between the emitter and matrix molecules as well as the formation of D/A exciplexes. Furthermore, the red RTP materials could be easily manufactured into diverse forms, including fine powders, aqueous inks, and nanoparticles. Their multifunctional applications in fingerprint recognition, encryption, and live bioimaging were demonstrated. With distinctive advantages such as red RTP, ultralong lifetime, scalable production, and cost-effectiveness, these RTP materials pave the way for the extensive utilization of organic RTP materials in various engineering sectors.