Eu (II) complex and application thereof as electroluminescent material
A technology of electroluminescent materials and electroluminescent devices, which is applied in the direction of luminescent materials, compounds containing elements of Group 3/13 of the periodic table, circuits, etc., and can solve problems such as poor thermal stability, long lifetime of excited states, and development lag.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0045] Preparation and Characterization of Example 1 Complexes Eu-1 and Eu-2
[0046] Sodium tris(3-trifluoromethylpyrazolyl)borate (NaTp CF3 ) or hydrogen tris (3-methylpyrazolyl) potassium borate (KTp CH3 ) and EuI 2 Stirring in THF gave Eu-1 and Eu-2 ( figure 1 ) The crude product of the complex was purified by thermal gradient sublimation to obtain the pure product of the complex. The pure product was identified by elemental analysis and single crystal X-ray diffraction (SCXRD, Table 1). Crystal structure data indicate that the central Eu in Eu-1 2+ The ions are coordinated by 6 nitrogen atoms and further protected by 6 fluorine atoms. The Eu-N and Eu-F bond lengths are about 2.72 and And the center Eu in Eu-2 2+ The ion has only 6 coordinating nitrogen atoms, but the Eu-N bond length is much shorter, about 2.60 to The space-filling model shows that, due to the presence of fluorine atoms, the central Eu in Eu-1 2+ Shielded works better. In order to quantitativel...
Embodiment 2
[0054] Preparation and Characterization of Example 2 Complexes Eu-3, Eu-4 and Eu-5
[0055] The three complexes of Eu-3, Eu-4 and Eu-5 were synthesized according to the following steps: the corresponding 1,3-propanedione and hydrazine hydrate were refluxed in ethanol to obtain pyrazole derivatives. Under the protection of nitrogen, slowly heat the pyrazole derivative and KBH 4 3:1 mixture until 3 equivalents of hydrogen are evolved, at which point the corresponding tripyrazole boron ligand is obtained. After purification, the ligand was mixed with europium iodide in THF to obtain the crude divalent europium pyrazole boron complex. The product is purified by sublimation or recrystallization. Ligands and complexes through 1 Characterization by means of H-NMR spectroscopy and elemental analysis.
[0056] Single crystals of Eu-3, Eu-4 and Eu-5 were obtained by slow evaporation of DCM / n-hexane mixed solution, toluene solution and slow sublimation, respectively. Characterized b...
Embodiment 3
[0065] Embodiment 3 electroluminescence device
[0066] In order to evaluate the application of Eu(II) complexes in OLEDs, this example uses Eu-1 as the light-emitting layer material for ITO / MoO 3 (2nm) / MoO 3 :1,3-bis(9H-carbazol-9-yl)benzene(mCP, 20wt%, 30nm) / mCP(10nm) / Eu-1:mCP(10wt%, 20nm) / 1,3,5-tris [(3-pyridyl)-3-phenyl]benzene (TmPyPB,40nm) / LiF(0.7nm) / Al(100nm)( Figure 5 a) Device. The device exhibits green emission with a λ max about 510nm ( Figure 6 ), the maximum EQE and brightness are 0.75% and 23cd m -2 ( Figure 5 b-c). Although the results exceed those of the only reported OLED based on Eu(II) complexes, this result was unexpected by the inventors of the present invention, especially considering the PLQY of 43% for the doped Eu-1:mCP film. In order to explore the root cause, an OLED with a similar structure using the traditional Ir(III) complex bis(4,6-difluorophenylpyridine) (picolinate) iridium (FIrpic) as the light-emitting layer was fabricated in this...
PUM
| Property | Measurement | Unit |
|---|---|---|
| thickness | aaaaa | aaaaa |
| luminance | aaaaa | aaaaa |
| luminance | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More