Aggregation-Induced Electrochemiluminescence of Carboranyl Carbazoles in Aqueous Media

Abstract

The aggregation-induced electrochemiluminescence (AIECL) of carboranyl carbazoles in aqueous media was investigated for the first time. Quantum yields, morphologies, and particle sizes were observed to determine the electrochemiluminescence (ECL) performance of these aggregated organic dots (ODs). All compounds exhibit much higher ECL stability and intensity than the carborane-free compound, demonstrating the essential role of the carboranyl motif. Moreover, the results of cyclic voltammetry (CV) suggest that oxidation/reduction reactions take place at the carboranyl motif. The excited states of ODs were proposed to be generated by the mechanism of surface state transitions. More importantly, these compounds show a reductive-oxidative mechanism in contrast to other organic materials that show oxidative-reductive mechanisms. Our experiments and data have established the relation between AIE organic structures and ECL properties that has a strong potential for biological and diagnostic applications.

Keywords: aggregation-induced emission; boron clusters; carborane; electrochemiluminescence; organic dots.