Reporting in the primary research journal Advanced Optical Materials (20 December 2021 https://doi.org/10.1002/adom.202101675), researchers from Paragraf and Queen Mary University of London have demonstrated the successful fabrication of an Organic Light-Emitting Diode (OLED) with a monolayer graphene anode, replacing ITO in organic light-emitting diodes.
Indium is one of the nine rarest elements in the Earth’s crust. It is on the EU’s list of critical materials. However, indium is widely used, mostly in the form of indium tin oxide (ITO), a key part of the touch screens on our mobile phones and computers. It is also used in flatscreen TVs and solar panels, and indium is an important element in the LED (light emitting diode) lights in our homes. Most homes will have many items that contain indium.
Led by Dr Ivor Guiney and Professor Sir Colin Humphreys, with Dr Zhichao Weng as the Research Fellow, the Innovate UK funded research utilising graphene opens the door to a radical change in the potential of high-tech devices of the future by removing a limiting ingredient, Indium.
Graphene is a single layer of carbon atoms. Carbon is very abundant in the Earth. Carbon is a sustainable material and indium is not. When it was discovered, in the form of small flakes, graphene was called the wonder material because of its amazing properties. However, organisations such as IBM, Intel and Samsung have been unable to scale-up the growth of graphene, so that it can be used in electronic devices. Paragraf has developed a new way to produce large-area graphene suitable for electronic devices.
Professor Humphreys of Queen Mary and Paragraf says “Because of its importance and scarcity there have been many attempts to replace ITO, but no material has been found to have a comparable performance in an electronic or optical device until now. Our paper is the first paper in the world to demonstrate that graphene can replace ITO in an electronic/optical device. We have shown that a graphene-OLED has an identical performance to an ITO-OLED. ITO-OLEDs are widely used as the touch screens on our mobile phones.”
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At Queen Mary University of London, we believe that a diversity of ideas helps us achieve the previously unthinkable. Throughout our history, we’ve fostered social justice and improved lives through academic excellence. And we continue to live and breathe this spirit today, not because it’s simply ‘the right thing to do’ but for what it helps us achieve and the intellectual brilliance it delivers. Our reformer heritage informs our conviction that great ideas can and should come from anywhere. It’s an approach that has brought results across the globe, from the communities of east London to the favelas of Rio de Janeiro. We continue to embrace diversity of thought and opinion in everything we do, in the belief that when views collide, disciplines interact, and perspectives intersect, truly original thought takes form.