Boosting Organic Afterglow Performance via a Two-Component Design Strategy Extracted from Macromolecular Self-Assembly.
Dahua LiMinjian WuXuefeng ChenJiahui LiuYan SunJu HuangYunlong ZouXuepu WangDaoyong ChenKaka ZhangPublished in: The journal of physical chemistry letters (2022)
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 (BF 2 bdk) and deuterated BF 2 bdk compounds for the fabrication of room-temperature organic afterglow materials. The polymer component can interact with BF 2 bdk excited states by dipole-dipole interactions, lower BF 2 bdk S 1 levels with insignificant effect on T 1 levels, reduce Δ E ST , and thus enhance intersystem crossing of BF 2 bdk excited states. The polymer component can also suppress intramolecular motion of BF 2 bdk triplets and protect BF 2 bdk triplets from oxygen quenching. The obtained BF 2 bdk-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.