Printable transparent electrodes for OLEDs and solar cells

The jointly funded project IMAGE (innovation printable electrode materials for high performance lighting devices and organic solar cells “IMAGE”) aimed to further the development of innovative printable, transparent electrode materials for high-efficiency OLEDs and solar cells. The electrodes need to be cost-effective, conductive, transparent, flexible, compatible and capable of being integrated in OLED or organic solar cells. The electrodes developed in project IMAGE could replace conventional transparent metal oxides, such as indium tin oxide (ITO), which are less flexible and less cost effective.

Developed by the Federal Ministry of Education and Research and the French Agence Nationale de la Recherche, the PEDOT-based electrodes are PSS free and provide transparency of up to 85% at 550nm, layer resistance of 90Ω/sq and conductivity of 200S/cm. Allowing integration on PET foils and PET foils with barrier films, the laser-structurable and OLED/OPV compatible electrodes offer improved rolling capacity compared to ITO-based electrodes.

Following the promising results of the project IMAGE, the IMAGE consortium is searching for industry partners for commercialisation. Film manufacturers and film refiners can use this opportunity to cooperate with material developers to make flexible transparent and conductive film products for numerous applications,such as in the field of photovoltaic, organic electronics or for touchscreens.

“We were able to construct the electrodes very thin, transparent and flexible and to integrate them in our processes. Thus Fraunhofer COMEDD is now in a position to manufacture flexible organic devices such as OLED lighting films, organic solar cells or sensors on film according to customer requirements," comments Dr. Olaf R. Hild, Business Unit Manager, Fraunhofer COMEDD.