Significantly Enhanced Afterglow Brightness via Intramolecular Energy Transfer

Afterglow materials with long-lived emission after ceasing the excitation source have exhibited tremendous potential for various applications. However, the inherently dim afterglow emission makes it a bottleneck for wider applications. Herein, we present an intramolecular energy transfer strategy for enhancing the afterglow brightness by covalently coupling of afterglow substrate unit and afterglow emitter unit. Compared to the conventional intermolecular energy transfer system, the afterglow intensity of our developed system based on intramolecular energy transfer shows an over 100-fold enhancement. Furthermore, we demonstrate the generality of this strategy for improving afterglow brightness, which is applicable to different afterglow materials including green, yellow, and red emissions. We believe that this strategy to enhance afterglow intensity will provide a major step forward for developing afterglow luminescent materials with high brightness.