8-Hydroxyquinoline aluminum salt
[CAS# 2085-33-8]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic aluminum
• Name: 8-Hydroxyquinoline aluminum salt
• Synonyms: Aluminium tris(quinolin-8-olate)
• Molecular Formula: C₂₇H₁₈AlN₃O₃
• Molecular Weight: 459.43
• CAS Registry Number: 2085-33-8
• EC Number: 218-227-0
• SMILES: C1=CC2=C(C(=C1)O[Al](OC3=CC=CC4=C3N=CC=C4)OC5=CC=CC6=C5N=CC=C6)N=CC=C2

Properties

• Melting point: 413-415 ºC

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319-H335
• Precautionary Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410

Discovory and Applicatios

8-Hydroxyquinoline aluminum salt is a coordination compound that plays a significant role in various fields, particularly in materials science and luminescent applications. The compound consists of aluminum coordinated with 8-hydroxyquinoline ligands, which are aromatic molecules containing a hydroxyl group and a nitrogen-containing heterocycle. This structure imparts unique properties to the compound, making it valuable in the development of advanced technologies such as organic light-emitting diodes (OLEDs), fluorescent sensors, and optoelectronics.

The discovery of 8-hydroxyquinoline aluminum salt can be traced back to early research on aluminum chelates, which aimed to develop materials with enhanced optical and electronic properties. The aluminum complex of 8-hydroxyquinoline was first synthesized in the mid-20th century, and its potential as a luminescent material was quickly recognized. The presence of the hydroxyl group in the 8-hydroxyquinoline ligand allows the compound to exhibit strong fluorescence, which has been explored for a wide range of applications in both academic and industrial settings.

One of the key applications of 8-hydroxyquinoline aluminum salt is in the field of OLEDs. OLEDs are widely used in displays, lighting, and other optoelectronic devices because of their ability to emit light efficiently when an electric current is applied. The compound serves as an efficient phosphorescent emitter in OLEDs, where it can produce bright and stable light. The aluminum coordination center plays a crucial role in stabilizing the electronic structure of the compound, while the 8-hydroxyquinoline ligands enhance its emission properties. By integrating 8-hydroxyquinoline aluminum salt into OLED devices, researchers have achieved higher brightness, longer operational lifetimes, and improved overall performance.

In addition to its use in OLEDs, 8-hydroxyquinoline aluminum salt has found applications in organic photovoltaic (OPV) devices. These devices, which convert sunlight into electricity, benefit from the compound’s electron-transporting properties. When incorporated into OPV cells, the compound improves the charge transport and efficiency of the devices, contributing to the development of more effective and affordable solar energy solutions. Its ability to facilitate electron movement while maintaining stability under various conditions makes it an attractive material for renewable energy technologies.

Another significant application of 8-hydroxyquinoline aluminum salt lies in the field of fluorescence sensing. The compound’s strong fluorescence emission when exposed to certain wavelengths of light makes it a suitable candidate for use in chemical and biological sensors. Its ability to selectively bind to metal ions and other chemical species enhances its utility in detecting environmental pollutants, metal contamination, and even biological molecules in medical diagnostics. Researchers continue to explore the potential of 8-hydroxyquinoline aluminum salt in sensor technologies, aiming to improve sensitivity and selectivity for various detection purposes.

Moreover, 8-hydroxyquinoline aluminum salt has been investigated for its potential in anticorrosive coatings. The compound’s ability to form stable complexes with metals and its inherent fluorescence properties have prompted research into its use as a protective coating for metal surfaces. The aluminum complex acts as a corrosion inhibitor by forming a protective layer on the surface, thus enhancing the longevity and durability of metal materials exposed to harsh environments.

As research on 8-hydroxyquinoline aluminum salt continues, new applications and formulations are being developed, particularly in areas such as environmental monitoring, energy harvesting, and biomedical imaging. Its versatility and unique properties make it a valuable compound in the ongoing quest for more efficient, sustainable, and innovative technologies.

References

2013. X-rays sensing properties of MEH-PPV, Alq3 and additive components: A new organic dosimeter as a candidate for minimizing the risk of accidents of patients undergoing radiation oncology. Medical Engineering & Physics, 35(1).
DOI: 10.1016/j.medengphy.2012.08.004

2017. Tunable organic distributed feedback dye laser device excited through F�rster mechanism. Applied Physics B, 123(4).
DOI: 10.1007/s00340-017-6679-x

2011. Sonochemical fabrication of 8-hydroxyquinoline aluminum (Alq3) nanoflowers with high electrogenerated chemiluminescence. Ultrasonics Sonochemistry, 18(2).
DOI: 10.1016/j.ultsonch.2010.06.005