Graphene proves its worth as transparent OLED electrodes

January 10, 2017 // By Julien Happich
Together with industrial partners, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP from Dresden has demonstrated the use of graphene in the production of transparent OLED electrodes. The research centre created an orange OLED with graphene electrodes measuring 20×10mm.

The graphene-based electrode production process was developed and optimized in the EU-funded project "Gladiator" (Graphene Layers: Production, Characterization and Integration) together with partners from industry and research.

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 about 800 degrees. 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. This process only takes a few minutes. After a cooling phase, a carrier polymer is placed on the graphene obtained and the copper plate is etched away.
The Gladiator project was launched in November 2013 and will reach its conclusion in April 2017. During the remainder of the project, researchers aim to minimize the impurities and defects which occur during the transfer of the wafer-thin graphene to another carrier material.

Industrial partners of the Gladiator project include Spanish company Graphenea S.A. responsible for the production of the graphene electrodes and British company Aixtron Ltd. responsible for the construction of the production CVD reactors.

"The first products could already be launched in two to three years", expects FEP’s project leader Dr. Beatrice Beyer. The large but ultra-thin and flexible graphene electrodes could find their way as a replacement for brittle ITO electrodes in touch screens, but also in photovoltaics.

Visit the Fraunhofer FEP at www.fraunhofer.de

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