Bis(8-hydroxy-2-methylquinoline)-(4-phenylphenoxy)aluminum, known as BAlq or BAlq3, is widely used as blue-emitting layer materials in organic light-emitting diodes. It is also used as hole-blocking layer or as a “barrier-softening” interfacial layer in between the electron transporting and emissive layers [1, 2, 3, 4].
BAlq is also applied as the host material and electron-transport type hole-blocking layer in red PHOLEDs, and to improve the efficiency and lifetime of PHOLEDs. As a hole-blocking material, it is known to allow for high lifetimes, up to 160,000 hours at a luminance level of 100 cd/m2 .
BAlq has a glass transition temperature of 99 °C and is photochemically stable .
|Molecular weight||512.53 g/mol|
|Absorption||λmax 259 nm (in THF)|
|Fluorescence||λem 334,477 nm (in THF)|
|HOMO/LUMO||HOMO = 5.9 eV, LUMO = 2.9 eV|
|Classification / Family||
Electron transporting materials, Hole blocking materials, Light emitter layer materials, Phosphorescent host materials, Organic light-emitting diodes, Organic electronics, Sublimed materials
|Melting point||Melting point/range: 207 - 214 °C (lit.)|
*Sublimation is a technique used to obtain ultra pure-grade chemicals. For more details about sublimation, please refer to the Sublimed Materials for OLED devices page.
|Device structure||ITO (110 nm)/NPB(80 nm)/BtpIr*-doped BAlq (47.5 nm)/Alq3(30 nm)/Li2O(0.5nm)/Al(100nm) |
|Max. Luminance||179 cd/m2|
ITO/CuPc (15 nm)/NPB (80 nm)/NPB: 0.5 wt% DCJTB (20 nm) /Alq3:0.5 wt% C545T (3 nm)/MADN:0.8 wt% DSA-ph*(40 nm)/BAlq3 (10 nm)/LiF/Al 
|Max. Luminance||45,000 cd/m2|
|Max. Current Efficiency||20.8 cd/A|
|Max. Power Efficiency||15.9 lm W−1|
ITO/MoOx (5 nm)/NPB (40 nm)/4% Y-Pt*:TCTA (20 nm)/8% FIrpic:mCP(10 nm)/8% FIrpic:UGH2 (10 nm)/BAlq (40 nm)/LiF (0.5 nm)/Al (100 nm) 
|Max. Current Efficiency||45.6 cd/A|
|Max. Power Efficiency||35.8 lm W−1|
*For chemical structure informations please refer to the cited references
Characterisation (TGA and DSC)
Literature and Reviews
- Electroluminescent properties of organic light-emitting diodes using BAlq and Alq3 co-evaporation layer, Y. Iwama et al., Thin Solid Films 499, 364-368 (2006).
- Electroluminescent mechanism of organic light-emitting diodes with blue-emitting Alq, T. Itoh et al., Colloids and Surfaces A: Physicochem. Eng. Aspects 284–285, 594–598 (2006).
- A host material containing tetraphenylsilane for phosphorescent OLEDs with high efficiency and operational stability, J-W. Kang et al., Org. Electronic, 9, 452–460 (2008).
- Electron transport in the organic small-molecule material BAlq — the role of correlated disorder and traps, S.L.M. van Mensfoort et al., Org. Electronic, 11, 1408–1413 (2010).
- Distinguished Paper: Red-Phosphorescent OLEDs Employing Bis(8-Quinolinolato)-Phenolato-Aluminum(III) Complexes as Emission-Layer Hosts, T. Tsuji et al., SID Symposium Digest of Technical Papers, 35 (1), 900-903 (2012).
- High efficiency fluorescent white organic light-emitting diodes with red, green and blue separately monochromatic emission layers, Z. Zhang et al., Org. Electronics, 10, 491-495 (2009); doi:10.1016/j.orgel.2009.02.006.
- High Efficiency White Organic Light-Emitting Devices Incorporating Yellow Phosphorescent Platinum(II) Complex and Composite Blue Host, S-L. Lai et al., Adv. Funct. Mater., 23, 5168–5176 (2013); DOI: 10.1002/adfm.201300281.
To the best of our knowledge the information provided here is accurate. However, Ossila assume no liability for the accuracy of this page. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. All products are for laboratory and research and development use only, and may not be used for any other purpose including health care, pharmaceuticals, cosmetics, food or commercial applications.