Optimized triple core blue emitters based on anthracene–pyrene–anthracene chromophores for organic light-emitting diodes

Three new fluorescent triple-core emitters were newly synthesized by attaching an optimized electron-donating group to an anthracene–pyrene–anthracene core moiety, resulting in 1,6-di(anthracen-9-yl)pyrene (DAP), 10,10′-(pyrene-1,6-diyl)bis(N,N-diphenylanthracen-9-amine) (DPA–DAP–DPA), and 4,4′-(pyrene-1,6-diylbis(anthracene-10,9-diyl))bis(N,N-diphenylaniline) (TPA–DAP–TPA). The photophysical, thermal, and electroluminescence properties of these synthesized materials were examined experimentally and theoretically. The triple-core derivatives were found to exhibit high thermal stability, with decomposition temperatures greater than 433 °C. DAP, DPA–DAP–DPA, and TPA–DAP–TPA showed deep-blue, sky-blue, and real blue photoluminescence emission, with maximum wavelengths of 430, 497, and 459 nm, respectively, in the solution state. Among the synthesized materials, TPA–DAP–TPA showed an excellent photoluminescence quantum yield of 77%. The device doped with TPA–DAP–TPA showed a high efficiency of 5.68 cd/A, CIE coordinates of (0.143, 0.151), and an external quantum efficiency of 4.64% at 10 mA/cm², indicating that the device has potential applications in mobile phones.