Graphene OLEDs pave way for unbreakable smartphone displays
Image credit: Fraunhofer FEP
Graphene organic light emitting diodes (OLED) have been created for the first time by a German-led research team paving the way for future unbreakable smartphone displays.
The team, led by researchers from the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology (FEP), believes the electrodes could be commercially available within two to three years.
The technology, relying on wonder properties of the single layer of graphene, could find widespread use in many applications ranging from consumer electronics to photovoltaics, medicine and high-tech textiles.
“This was a real breakthrough in research and integration of extremely demanding materials,” said FEP’s project leader Beatrice Beyer.
To create the OLED electrodes, some 2 by 1 square centimetres in size, the team developed a process, during which wafers of high-purity copper are heated to about 800°C inside a vacuum chamber. A mixture of methane and hydrogen is then added, initiating a chemical reaction during which the methane dissolves in the copper forming carbon atoms. Within a few minutes, the carbon atoms deposit evenly on a surface from where they are transferred after cooling down onto a carrier polymer.
The Fraunhofer team develop the graphene OLEDs together with industrial partners as part of the EU-funded project Gladiatior. The project, launched in 2013, officially ends in April this year, by which time the team hopes to fine-tune the process and minimise the amount of defects and impurities in the product.
Graphene, first created by Manchester University scientists Andre Geim and Konstantin Novoselov in 2004, is a single layer of carbon atoms arranged in a honeycomb structure. Its 2D structure gives graphene some unique properties. It is at the same time extremely hard yet flexible and transparent. It also conducts heat and electricity exquisitely, which makes it promising for applications in next generation electronics.
Due to the material’s flexibility, the graphene electrodes would be ideal for the manufacture of smartphone touch screens that don’t break when the owner drops the phone. Inn windows, graphene could be used to regulate the light transmission or serve as an electrode in polarisation filters.