Scientists have produced the first functional organic light-emitting diode (OLED) electrodes from graphene.
The process was developed by Fraunhofer researchers together with partners from industry and research.
The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology (FEP) in Dresden, Germany, together with partners, has succeeded for the first time in producing OLED electrodes from graphene.
FEP’s project leader Dr Beatrice Beyer said: “This was a real breakthrough in the research and integration of extremely demanding materials.”
The process was developed and optimised under the EU-funded project ‘Gladiator’ (Graphene Layers: Production, Characterisation and Integration).
Graphene consists of a single layer of carbon atoms which are assembled in a kind of honeycomb pattern. It is only 0.3 nanometres thick, which is about one hundred thousandth of a human hair.
The production of the OLED electrodes takes place in a vacuum. In a steel chamber, a wafer plate of high-purity copper is heated to around 800°. The research team then supplies a mixture of methane and hydrogen and initiates a chemical reaction. The methane dissolves in the copper and forms carbon atoms, which spread on the surface. After a cooling phase, a carrier polymer is placed on the graphene and the copper plate is etched away.
During the remainder of the project, impurities and defects which occur during the transfer of the graphene to another carrier material are to be minimised.
Beyer added: “The first products could already be launched in two to three years.”
The project is supported by the EU Commission with a total of €12.4m and will run until April 2017.