The use of organic light-emitting diodes (OLEDs) in diverse flat-panel display technologies, including smartphones and large-screen televisions, has attracted considerable attention [1]. OLEDs provide several benefits, such as simplified development, rapid response time, extensive viewing angles, little energy usage, compatibility with flexible plastic substrates, and a variety of form factors appropriate for different display kinds [2]. The incorporation of imidazole derivatives as acceptors with fluorene as a donor may facilitate efficient charge transfer, perhaps enhancing the singlet exciton yield. The compounds of imidazole and fluorene are anticipated to serve as effective deep blue luminophores. Moreover, the addition of sterically large substituents at the C-9 position of the fluorene moiety diminishes the overlap of frontier molecular orbitals and electron exchange with adjacent molecules, thereby facilitating the maintenance of a high photoluminescence quantum yield in the solid state. [1, 3].
This work included the synthesis and examination of several derivatives of imidazole and fluorene-based compounds as prospective materials for blue OLEDs. The thermal and photophysical analysis of these materials indicated that the synthesized compounds exhibited high-intensity emission with brief emission lifetimes ranging from 1.54 to 7.63 ns, positioning them as attractive candidates for rapid-response OLEDs. Furthermore, they exhibited significant thermal stability and formed molecular glasses with elevated glass transition temperatures of 130°.