24.3: High Efficient Persistent Luminescence from F�rster resonance Energy Transfer Processes

Metal‐free organic systems with persistent room temperature phosphorescence (pRTP) have attracted considerable attention due to their long‐lived emission (over 0.1 s) after removal of the excitation, plus their advantages of good biocompatibility and facile functionality. [1] Thus, organic pRTP materials show great potential applications in bioimaging, information storage, and optical sensing. A variety of organic pRTP materials have been developed by promoting the intersystem crossing and suppressing the non‐radiative decay as much as possible. However, their pRTP emissions were generally in the spectral region of below 600 nm, for whether crystalline phosphors or polymeric systems, let alone emission in NIR region of over 750 nm. [2]