Green iridium complexes based on pyrimidine derivatives for efficient electroluminescence with EQE near 30%
| Autor: | Hua-Bo Han, Zhen-Long Tu, Zheng-Guang Wu, You-Xuan Zheng |
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| Rok vydání: | 2019 |
| Předmět: |
Electron mobility
Trifluoromethyl Photoluminescence Materials science Process Chemistry and Technology General Chemical Engineering Quantum yield chemistry.chemical_element 02 engineering and technology Electroluminescence 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences chemistry.chemical_compound chemistry OLED Physical chemistry Quantum efficiency Iridium 0210 nano-technology |
| Zdroj: | Dyes and Pigments. 160:863-871 |
| ISSN: | 0143-7208 |
| DOI: | 10.1016/j.dyepig.2018.09.017 |
| Popis: | To obtain dopants owing excellent electron mobility, four novel iridium (III) complexes (Ir(tfmppm)2(acac), Ir(tfmppm)2(tpip), Ir(f-4-tfmppm)2(tpip) and Ir(f-3-tfmppm)2(tpip)) with green emission using 2-(2,6-bis(trifluoromethyl)pyridin-4-yl)pyrimidine (tfmppm), 2-(2,6-bis(trifluoromethyl)pyridin-4-yl)-5-fluoropyrimidine (f-4-tfmppm) and 2-(2,6-bis(trifluoromethyl)pyridin-3-yl)-5-fluoropyrimidine (f-3-tfmppm) as main ligands, acetylacetonate (acac) and tetraphenylimidodiphosphinate (tpip) as ancillary ligands, were investigated, respectively. Due to the variation of the structures among the complexes, the photoluminescence quantum yield (up to 94%) and electron mobility can be regulated gradually, which would broaden the recombination zone, balance the distribution of holes and electrons, leading to excellent electroluminescence (EL) performances. Among four emitters, the organic light-emitting diodes (OLEDs) using Ir(f-3-tfmppm)2(tpip) display the best EL performances with a maximum current efficiency of 92.83 cd A−1 and a maximum external quantum efficiency of 29.5%, suggesting these materials have potential application in OLEDs. |
| Databáze: | OpenAIRE |
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