Researchers at the Universities of Basel and Valencia have reported important advances in the development of next generation lighting technologies in the journal “Chemical Science”.
Lighting technology is in a state of change. The old-fashioned light-bulb, which was more efficient at converting electricity into heat than light, is currently being replaced by fluorescent devices and it is expected that light emitting diodes (LEDs) will be the technology of choice in the mid-term future.
The research group lead by Basel professors Catherine E. Housecroft and Edwin C. Constable describes the design of new molecular components and strategies for the preparation of light-emitting electrochemical cells (LECs) with remarkable lifetimes.
Simpler and less demanding LECs
LEDs have the disadvantage that they are complex, multilayered devices that require high-vacuum and high temperature techniques for their preparation. They also need to be rigorously protected from exposure to air or water. LECs are much simpler devices, comprising only one layer of active material, which can be solution-processed in ambient conditions.
To date, LEC devices have had relatively short lifetimes which have precluded serious commercial investigation. The Basel and Valencia teams have shown that devices with lifetimes exceeding 2500 hours can now be prepared using molecular components stabilized by so-called aromatic rings.
The team has built metal complexes decorated with rings that arrange themselves to form a shell around the molecule. “It is a little bit like a flower closing up at night – the flat, petal-like rings fold up about the metal to make a compact and robust structure”, says Constable.
These supramolecular interactions make the complexes exceptionally stable. Furthermore, molecular tuning of the components allows a tuning of the color of light emitted, bringing the goal of white-light emitting devices one step closer.
Andreas M. Bünzli, Edwin C. Constable, Catherine E. Housecroft, Alessandro Prescimone, Jennifer A. Zampese, Giulia Longo, Lidón Gil-Escrig, Antonio Pertegás, Enrique Ortí and Henk J. Bolink
Exceptionally long-lived light-emitting electrochemical cells: multiple intra-cation π-stacking interactions in [Ir(C^N)2(N^N)][PF6] emitters
Chem. Sci., 2015, 1-10 | doi: 10.1039/c4sc03942d
Edwin C. Constable, Department of Chemistry, University of Basel, Tel. +41 61 267 10 01, Email: firstname.lastname@example.org
Catherine E. Housecroft, Department of Chemistry, University of Basel, Tel. +41 61 267 10 08, Email: email@example.com
Olivia Poisson | Universität Basel
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy