Electroluminescent applications of a cyclic carbazole oligomer

Abstract

A cyclic carbazole oligomer for organic light-emitting diodes is described. This cyclic oligomer has a high glass transition temperature (105 °C ), and high quality amorphous film can be prepared by the conventional spin-coating technique. We examined the characteristics of this cyclic oligomer for electron transport layer applications. The device structure of indium tin oxide/hole transport layer/electron transport layer/Al was used. The EL device exhibited green light with a luminance of 60 cd m−2 at 15 V and the external quantum efficiency was 0.44%. tuted carbazole main-chain17 and hyperbranched polymers18

Crystal structures, optical properties and theoretical calculation of novel two-photon polymerization initiators

“…These bands can be assigned to the excimer emission of the compounds due to the interactions between the molecules. Most carbazole compounds emit at wavelengths >400 nm in solid state [45][46][47] due to the aromatic p-p stacking. One sees that the fluorescence peak in Fig.…”

Synthesis of two carbazole-based dyes and application of two-photon initiating polymerization

“…Compounds 1−3 were synthesized according to the reported methods [16,17] . Scheme 1 Strategy of synthesis of the target compounds.…”

The synthesis, characterization and electroluminescent properties of zinc(II) complexes for single-layer organic light-emitting diodes

“…Carbazole derivatives are well known as hole-transporting and electroluminescent structure, because of their high charge mobility and photochemical stability, and because of their blue electroluminescence as a result of large band gap (improved planar biphenyl unit by the bridging nitrogen atom) [4,5]. In addition, the carbazole derivatives can be readily functionalized at 3-, 6-, or 9-position and covalently linked to other molecular units [6][7][8][9][10], resulting in a versatile synthesis of many types of derivatives. Substituting the hydrogen atom on nitrogen atom with alkyl chains, such as 2-ethylhexyl bromide and octylbromide, can increase the solubility of carbazole derivatives [4,11].…”