This review focuses on fused-ring carbazole derivatives, their molecular design, electronic and photophysical properties, and their applications as the emitter and/or the host material in organic light emitting diodes (OLEDs).
A series of pyridinium–indolocarbazole oligomers has been synthesized, which fold into helical structures with tubular cavities capable of accommodating up to four iodide ions in a linear arrangement.
A protocol for mono-substitution of quinoxalines/ quinoxaline-2(1H)-ones with indoles and lead to indolocarbazole-quinoxalines with good yields under transition metal-free conditions.
A novel narrowband multi-resonance emitter obtained by incorporating B–N covalent bonds and extending π-conjugation via a simplified lithium-free one-pot borylation reaction achieved a redshifted sky-blue emission at 484 nm with a FWHM of 19 nm.
A design strategy for efficient MR-TADF emitters needs (i) avoiding aggregation by inducing steric hindrance at peripheral strategic positions, and (ii) combining lateral groups of higher donor character as compared to the central core.