Solution-processable 1,3,5-tri(9-anthracene)-benzene cored propeller-shaped materials with high Tg for blue organic light-emitting diodes

Abstract

This study describes the synthesis and characterization of a series of new blue fluorescent materials, with propeller-like topology, consisting of 1,3,5-tri(9-anthracene)benzene core and various aromatic dendrons, such as naphthalene, 3,5-diphenylbenzene, carbazole, and N, N-diphenylamine. These compounds show excellent thermal and morphological stability with high glass transition temperatures ( T g) (166–231 °C) and high thermal decomposition temperatures ( T d) (427–504 °C). Solution-processable double-layered OLEDs fabricated with these materials as the light-emitting layer show stable blue emission and good performance. The nondoped electronic device fabricated using compound 5c exhibits a maximum brightness of 4754 cd/m 2 and maximum current efficiency of 2.0 cd/A (power efficiency, 1.71 lm/W) with Commission Internationale d’Eclairage (CIE x,y ) color coordinates of ( x = 0.16, y = 0.19) and the devices’ threshold voltage are only 3.4 eV. Compound 5d shows an even higher efficiency of up to 4.90 cd/A with CIE x,y color coordinates of ( x = 0.17, y = 0.31) when doped with a blue fluorescent dopant, 4,4′-bis[4-(di-p-tolylamino)styryl]biphenyl ( DPAVBi).