Two-component design strategy: TADF-Type organic afterglow for time-gated chemodosimeters

Organic afterglow materials exhibit strong capability to avoid fluorescence interference for their applications in highly sensitive analysis. However, afterglow materials with specific analysis properties are less explored. For example, among the reported studies, afterglow materials with chemodosimeter functions towards specific substances remain elusive even in a proof-of-concept demonstration level. The key to address this issue is to develop reactive organic dyes that can be processed into room-temperature afterglow materials. Here, by doping reactive pyrylium salts into phenyl benzoate matrices, we report the fabrication of TADF-type organic afterglow materials which feature a moderate kRISC of 100-102 s−1 to efficiently harvest triplet energies, significantly improve afterglow efficiency and simultaneously maintain afterglow emission lifetimes. The obtained materials possess afterglow quantum yields up to 48%, which is among the highest values in the reported studies, and can function as time-gated chemodosimeters specifically towards amine-containing compounds even in the presence of strong fluorescence backgrounds.