Synthesis, Electroluminescent Properties of 2-[2-(9-Aryl-9H-carbazol-3-yl)vinyl]-8-hydroxyquinoline and Their Each Zinc(II) Complexes

The (E)-2-[2-(9-p-tolyl-9H-carbazol-3-yl)vinyl]-8-hydroxyquinoline(8), (E)-2-{2-[9-(4-methoxyphenyl)-9H-carbazol-3-yl]vinyl}-8-hydroxyquinoline(9) and their zinc(11) complexes (10 and 11) were synthesized and confirmed by UV-Vis, FTIR, ESI-MS, FAB-MS, H-1 NMR and elemental analysis. The thermal analysis results indicate that complexes 10 and 11 have good thermal stability, which is very essential for fabricating stable organic electroluminescent devices. The single-layer OLEDs with structure of ITO/Organ layer(50 nm)/Al(100 nm) were prepared based on them all emit yellow, in which the peak emission of electroluminescent were 592, 583 nm individually. The OLED based on complex 10 exhibited better device performance with a maximum luminance of 489 cd/m(2) and luminance efficiency of 0.41 cd/A than those of the device fabricated by complex 11, which were 402 cd/m(2), and 1.81 cd/A. The electroluminescent studies carried out on the two newly synthesized Zn(II) complexes clearly demonstrate that fine control of the electroluminescent properties is possible through the modification of substitute in position 2 of the 8-hydroxyquinoline rings.