Synthesis and electroluminescent properties of a novel electroluminescence material of bis-2-(4-(diphenylphosphino)phenyl)benzo[d]oxazole (DPB).

A new light-emissive material, bis-2-(4-(diphenylphosphino)phenyl)benzo[d]oxazole (DPB), has been synthesized and characterized by FT-NMR, FT-IR, UV-Vis and elemental analysis. DPB has the band gap of 4.3 eV between HOMO and LUMO levels. The photoluminescence (PL) of DPB was measured at 410 nm from the chloroform solution. The electroluminescent (EL) devices with structures of ITO/NPB/DPB/LiF/Al and ITO/NPB/DPB/Alq3/LiF/Al were constructed and showed maximum emission at 540 nm. The device using DPB as emitting material showed the luminance of 1000 cd/m2 at 11 V. The CIE chromaticity of the device showed near the region of white color emission.

Zinc complex based on 2-(5-methyl-2-hydroxyphenyl)benzotriazole: synthesis and electroluminescence characteristics.

Zinc (II) [2-(5-methyl-2-hydroxyphenyl)benzotriazole] (Zn(MHB)2) was synthesized and characterized by FT-NMR, FT-IR, UV-Vis, XPS and elemental analysis. The photoluminescence of Zn(MHB)2 was measured at 516 nm from the DMF solution. The HOMO (6.6 eV) and LUMO (3.1 eV) energy levels of Zn(MHB)2 were estimated from the measurement of cyclic voltammetry. The devices with structure of ITO/NPB/Zn(MHB)2/Alq3/LiF/Al were constructed to investigate their electroluminescent (EL) performance. Zn(MHB)2 was found to be a good hole-blocking material in the EL devices.