Methodologies for constructing multi-color room temperature phosphorescent systems

Room temperature phosphorescent (RTP) materials have attracted much attention due to their potential applications to anti-counterfeiting encryption, optoelectronic devices and biological imaging. While the development of long lifetime afterglow materials is being promoted, the construction of multi-color afterglow materials by modulating the excited state energy through different means is also important. However, the sensitivity of the excited state and the transition mechanism of T₁ result in the limitation of afterglow colors. Therefore, the methods of constructing multi-color RTP materials are summarized into six categories: push–pull electron effect, π-conjugation, molecular aggregation state, multi-component doping, supramolecular self-assembly and multi-mode emission. Based on methodological guidance, the potential applications of multi-color RTP in the fields of optical information storage, bioimaging and intelligent response systems are also discussed. Finally, the construction of multi-color RTP materials is prospected to provide valuable references for the further development of multi-color afterglow regulation methodologies.