Tricarbazole-based donor–acceptor architectures with diverse acceptors: synthesis, properties and applications

Abstract

Herein, using tricarbazole as the electron donor and four aromatic rings with varied electron cloud density as acceptor, four homologous donor-acceptor (D–A) architectures (TrCzDAa~d) were divergently synthesized and characterized. Their steady-state and transient photophysical properties were subsequently investigated, in which their intramolecular charge transfer transitions were disclosed by solvent-dependent fluorescence spectra. Interestingly, the electron-rich acceptor could result in the blue shift of fluorescence, while the electron-deficient acceptor led to red-shifted fluorescence emission.Furthermore, intense and stable electrochemiluminescence (ECL) signals were observed for all architectures. In contrast, the ECL intensity enhanced with the increasing electron cloud density of the acceptor. Finally, TrCzDAb displaying the optimal ECL performance, was used as the electrode modification material to construct an epinephrine sensor, which demonstrated high sensitivity, excellent stability, and remarkable selectivity. This work elucidated the regulatory role of electron cloud density of the acceptor on the optoelectronic properties of D–A architectures and provides new insights for developing novel high-performance optoelectronic materials and sensors.