Dynamics of Pyrene Excimer in a Cholesteryl‐based Supramolecular Host Matrix
Aggregation‐caused quenching (ACQ) reduces luminescence and compromises brightness in solid‐state displays, necessitating strategies to mitigate its effects for enhanced performance. This study presents cost‐effective method to mitigate ACQ of pyrene by co‐assembling polycyclic aromatic hydrocarbons within low molecular weight gelator. Synthesized from readily available materials – cholesteryl chloroformate and pentaerythritol – in one‐step reaction, gelator incorporates four cholesteryl units, reported to promote robust supramolecular gels in various solvents. Encapsulation of pyrene in a supramolecular host has effectively addressed the challenge of ACQ in the solid‐state. Utilizing steady‐state and time‐resolved spectroscopic techniques, we probed the excimer formation dynamics across solution, powder, and xerogel phases. Through time‐resolved emission spectra (TRES) and time‐resolved area‐normalized emission spectra (TRANES), we observed the monomer‐to‐excimer transition under various conditions. In solution, this transition occurs in a single step, characterized by a single isoemissive point (~443 nm) observed in TRANES. In powder, two isoemissive points (~445 nm and ~485 nm) were observed, indicating more complex process with an additional relaxed or trap state. The xerogel phase revealed an intricate excimer formation pathway, involving three isoemissive points (~418 nm, ~442 nm, and ~423 nm). These observations suggest multiple intermediate states in monomer‐excimer transition and distinct dynamics in the solid matrix.