Long-Lived Emissive Hydrogen-Bonded Macrocycles: Donors Regulating Room-Temperature Phosphorescence and Thermally Activated Delayed Fluorescence

摘要

Despite vast applications of macrocycles in supramolecular chemistry,achieving long-lived emissions including room-temperature phosphorescence(RTP) or thermally activated delayed fluorescence (TADF) for potentialuse still presents a great challenge. This work first reports hydrogen-bonded(H-bonded) macrocycles emitting RTP and TADF by introducing variousdonors onto the same aramide skeleton containing a rigid acceptor. Theformation of charge transfer effectively enhances the photoluminescenceefficiency. Aromatic carbonyl groups promote the intersystem crossing. Thedrastically reduced flexibility of chromophores fixed by the H-bonded macrocyclicframework contributes to suppress the nonradiative decay to stabilizetriplet excitons. Therefore, RTP and TADF are acquired by altering donors,and are systematically revealed by comparisons with control compounds andtheoretical calculations. Finally, near white-light emission (CIE, 0.30, 0.33) isrealized via host–guest interactions.