Boosting Organic Afterglow Performance via a Two-Component Design Strategy Extracted from Macromolecular...

Because intersystem crossing and phosphorescence decay are spin-forbidden in organic systems, it is challenging to obtain high-performance organic afterglow materials. Inspired by two-component design strategy from macromolecular self-assembly, here we report the utilization of synthetic polymers to control the excited state properties of difluoroboron β-diketonate (BF₂bdk) and deuterated BF₂bdk compounds for the fabrication of room-temperature organic afterglow materials. The polymer component can interact with BF₂bdk excited states by dipole-dipole interactions, lower BF₂bdk S₁ levels with insignificant effect on T₁ levels, reduce ΔE_ST, and thus enhance intersystem crossing of BF₂bdk excited states. The polymer component can also suppress intramolecular motion of BF₂bdk triplets and protect BF₂bdk triplets from oxygen quenching. The obtained BF₂bdk-polymer afterglow materials exhibit emission lifetimes up to 2.2 s and high photoluminescence quantum yields under ambient conditions, display excellent processability and flexibility, and can function as efficient donors for excited state energy transfer to construct red afterglow materials.