Researchers from the Institute of Physical Chemistry of the Polish Academy of Sciences (IChF PAN) and Warsaw University of Technology, led by Prof. Janusz Lewiński, have developed a new class of efficient light-emitting materials. These compounds exhibit unique properties that make them highly promising candidates for practical applications in optoelectronic devices.
The growing demand for artificial light has intensified research into luminescent materials—compounds that emit light when excited—and their use in energy-efficient technologies such as optical sensors, displays, and bioimaging. As a result, scientists around the world are actively seeking novel and more efficient materials to enhance lighting technologies.
In recent years, metal complexes based on main-group elements of the periodic table have attracted increasing attention. One major advantage of such complexes is the ability to fine-tune their photophysical properties through structural modification.
Since the breakthrough use of Alq3 (tris(8-hydroxyquinolinato)aluminium) in LEDs in 1987, aluminium-based complexes have been explored for their promising photophysical properties, particularly in OLEDs and light-emitting sensors. Aluminum’s abundance in the Earth’s crust further supports its appeal in materials science.
Recently, scientists from IChF PAN and Warsaw University of Technology, in collaboration with Prof. Andrew E. H. Wheatley from the University of Cambridge, have developed a new class of highly-luminescent organoaluminium complexes.
The results were published in Angewandte Chemie International Edition:
“Inspired by previous research and benchmark materials like Alq₃, the researchers synthesized a new series unique tetrameric chiral-at-metal alkylaluminium anthranilates [(R′-anth)AlR]4 incorporating common anthranilates as a core ligand. These aluminium-based complexes demonstrate promising optoelectronic properties” notes the IChF PAN press release.
Comprehensive physicochemical studies, including detailed analysis of photoactivity, revealed that the aluminium-based anthranilates exhibit photoluminescence quantum yields of up to 100% in the solid state, enabled by their unique electronic structure and non-covalent interactions that stabilize excited states. Subtle ligand modifications were shown to significantly boost emission efficiency, opening new pathways for designing advanced photoactive materials.
“By changing the N-substituents from H to Me and Ph, we have developed a series of luminophores that exhibit poor-to-excellent performance, providing a [(Ph-anth)AlEt]4 derivative that achieves a unity photoluminescence quantum yield in the condensed phase, which is unprecedented for aluminium complexes.” – remarks Dr. Iwona Justyniak
The presented work is an important step forward the design of the novel, easily accessible effective fluorescent materials. The simplicity of the ligand framework modification offers the possibility of further upgrading of the system to achieve greater chemical stability and enables modulation of the optical properties which brings us closer to make it useful in practical applications, especially in technologies like OLEDs, display screens, and sensors.
The research was funded by the National Science Centre (NCN), Poland, under the OPUS 19 grant.
Ph: Grzegorz Krzyżewski
Source:
Nauka w Polsce
Institute of Physical Chemistry, Polish Academy of Sciences
