Carbazole-Derived Group of Uniform Materials Based on Organic Salts: Solid State Fluorescent Analogues of Ionic Liquids for Potential Applications in Organic-Based Blue Light-Emitting Diodes

In this study, we report synthesis and characterization of novel carbazole-based group of uniform materials based on organic salts (GUMBOS), as well as potential applications of these compounds. These organic-based compounds exhibit high thermal stability (decomposition temperatures in the range of 395–432 °C) and photostability. In addition, these compounds have appreciably high fluorescence quantum yields (73–99%) with broad emissions in the visible region and quantum yields which depend on the GUMBOS counteranion. The physicochemical, optical, and electrochemical properties of these materials are investigated and detailed here. Evaluation of band gap values (3.4 eV), HOMO–LUMO energy levels, and measured fluorescence quantum yields as compared to carbazole suggest potential use in organic light-emitting diodes. Computational results are found to be complementary to experimental results, and calculated band gaps are in agreement with experimentally obtain values.