Tunable Thermally Activated Delayed Fluorescence from Supramolecular Polymers Toward Application in Aqueous Media

Thermally activated delayed fluorescence (TADF) offers great potential for application in light emitting devices and bioimaging. Supramolecular polymers can offer intriguing properties for the same applications, such as stimuli responsiveness and self-healing owing to their dynamic intermolecular interactions. However, merging the two has remained a formidable challenge, due to the nonplanar geometry of common TADF chromophores. Herein, we overcome this challenge by utilizing a less distorted multiple resonance TADF (MR-TADF) chromophore connected to a polymerization inducing building block. The obtained supramolecular synthon is capable of assembling in aliphatic solvents due to combined interchromophore interactions and hydrogen bonding. Within the supramolecular ensemble the long-lived photoluminescence properties of the chromophore are maintained. Further modification of the photoluminescence properties could be achieved by using different supramolecular modulators in a social self-sorting approach, allowing fine-tuning of the photoluminescence lifetime and bandwidth. Notably, the extent of intermolecular interactions can switch these assemblies from kinetically to thermodynamically controlled regimes. Finally, we employ this co-assembly strategy to move from organic to aqueous media highlighting the potential toward biological applications.