The Effect of Molecular Structure on the Properties of Fluorene Derivatives for OLED Applications

Abstract

A new family of symmetrical fluorene derivatives with different types of substituents attached to the C-2 and C-7 positions of the fluorene core synthesized by the Sonogashira coupling reactions is reported. The electronic structures and the properties of the compounds investigated by means of photoelectron emission spectroscopy, UV–Vis absorption and photoluminescent spectroscopy as well as by DFT and TD-DFT theoretical calculations are discussed. It is shown that the nature of substituents influences the π-conjugation of the molecules. No intermolecular charge transfer within the investigated wavelength range is observed. The applicability of the synthesized compounds in organic light-emitting diodes (OLEDs) based on exciplex emission is demonstrated. The advanced co-deposition technique with the tuned OLED architecture was applied and resulted in improved OLED parameters. © 2024 by the authors. --//-- This is an open access article Pidluzhna, A.; Vembris, A.; Grzibovskis, R.; Zommere, M.A.; Bezvikonnyi, O.; Simokaitiene, J.; Baronaite, M.; Volyniuk, D.; Grazulevicius, J.V.; Ali, A.; et al. The Effect of Molecular Structure on the Properties of Fluorene Derivatives for OLED Applications. Molecules 2024, 29, 4918, https://doi.org/10.3390/molecules29204918 published under the CC BY 4.0 licence.