| Autor: |
Arunandan Kumar, Ritu Srivastava, Vandna Nishal, Modeeparampil N. Kamalasanan, Pratap Singh Kadyan, Ishwar Singh, Amit Kumar |
| Rok vydání: |
2013 |
| Předmět: |
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| Zdroj: |
Journal of Organometallic Chemistry. 740:116-122 |
| ISSN: |
0022-328X |
| DOI: |
10.1016/j.jorganchem.2013.04.032 |
| Popis: |
Ternary zinc complexes: [2-(2-hydroxyphenyl)benzoxazolato]5-chloro-8-hydroxy quinolinatozinc(II) [Zn(HPB)(Clq)] and [2-(2-hydroxyphenyl)benzoxazolato]5,7-dichloro-8-hydroxyquinolinatozinc(II) [Zn(HPB)(Cl 2 q)]) were synthesized and characterized as electroluminescent materials. These complexes possessed high thermal stability (>300 °C) and high glass transition temperature (>150 °C). The excited state lifetime of these complexes measured by transient photo-luminescence spectroscopy showed 4.19, 11.02 ns and 2.67, 10.7 ns for Zn(HPB)(Clq) and Zn(HPB)(Cl 2 q), respectively. The electroluminescence spectra showed peak emission centered at 549 and 554 nm, respectively, for these materials. Both the molecules were found to be quite efficient in a multilayered device structure ITO/α-NPD/Zinc complex/BCP/Alq 3 /LiF/Al with yellow emission having Internationale d'Eclairage (CIE) coordinates x = 0.37 and y = 0.57 for Zn(HPB)(Clq); and x = 0.40 and y = 0.56 for the Zn(HPB)(Cl 2 q) complex. Electron mobilities of these molecules were found to be 3 × 10 −6 –7 × 10 −6 s for electric field range 1000–1200 (V/cm) 1/2 . These molecules showed very high efficiency as electron transport layer with device structure ITO/α-NPD/5% Ir(ppy) 3 doped CBP/BCP/Zn(HPB)(Clq) or Zn(HPB)(Cl 2 q)/LiF/Al and therefore are better electron transporters as compared to Alq 3 in a device structure of ITO/α-NPD/5% Ir(ppy) 3 doped CBP/BCP/Alq 3 /LiF/Al. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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