Printed Transparent Electrodes for Flexible OLEDs

The BMBF-funded project IMAGE for the development of innovative printable electrode materials for high-efficient organic light-emitting diodes and solar cells has been successfully completed.
Flexible organic light-emitting diodes (OLED) with transparent electrodes © Fraunhofer COMEDD
Flexible organic light-emitting diodes (OLED) with transparent electrodes. Photo  Fraunhofer COMEDD

Progress in the development of flexible, transparent electrodes for OLED, OPD and OPV.

After working together for 3 years, the jointly funded project IMAGE (innovation printable electrode materials for high performance lighting devices and organic solar cells) has been successfully completed by the German Federal Ministry of Education and Research and the French Agence Nationale de la Recherche. As a result, the project partners Carnot MIB from Bordeaux (project lead by LCPO) and Fraunhofer COMEDD from Dresden demonstrated novel transparent electrodes which are arranged on a backing film and enable flexible electronic components.

The performance of these electrodes, which are made up of organic materials, was demonstrated by using flexible OLED and organic solar cells. The objective of the IMAGE project was the development of innovative printable, transparent electrode materials for high-efficiency organic light-emitting diodes and solar cells. This should be cost-effective, conductive, transparent, flexible, compatible and capable of being integrated in OLED or organic solar cells. The electrodes developed in IMAGE should replace conventional transparent metal oxides, such as indium tin oxide (ITO), which are less flexible and less cost effective.

Dr. Olaf R. Hild, business unit manager at Fraunhofer COMEDD, explains the significant results as follows:
“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.

Technical results at a glance:

  • PEDOT-based electrodes, PSS free
  • Transparency @ 550 nm up to 85 %
  • Layer Resistance: 90 ohms/sq.
  • Conductivity: 200 Scm-1
  • Integration on PET foils and PET foils with barrier films
  • Laser-structurable
  • OLED/OPV compatible
  • Improved rolling capacity compared to ITO-based electrode

Subsequent to the promising results of the  IMAGE project, the consortium is now looking for industry partners for commercialization. Especially film manufacturers and film refiners can take this opportunity to cooperate with material developers in order to make flexible transparent and conductive film products for numerous applications, e. g. in the field of photovoltaic, organic electronics or for touchscreens, ready for the market.

The IMAGE consortium

The partners from MIB were responsible for the development of suitable chemical compositions and solutions for the production of transparent organic electrodes. Fraunhofer COMEDD developed the structuring procedures and integrated OLED and organic solar cells in the novel electrodes and developed encapsulation technologies.

The chemical company Arkema and lighting company Tridonic provided advisory support to the project consortium during the project duration.

Carnot MIB institute (University of Bordeaux, FRANCE):
Leader: LCPO (Laboratoire de Chimie des Polymères Organiques);
Principal coordinator : Prof. Georges Hadziioannou (
IMS (Laboratoire de l’Intégration du Matériau au Système)
CRPP (Centre de Recherche Paul Pascal)

This project was funded by the German Federal Ministry of Education and Research and the Agence Nationale de la Recherche in joint program “Inter Carnot Fraunhofer”.

About Fraunhofer COMEDD

The Fraunhofer Research Institution for Organics, Materials and Electronic Devices COMEDD was founded as an independent research institution of the Fraunhofer-Gesellschaft in order to transfer the results of research and development in the field of organic materials and systems to production.

About the Carnot Institute

The Carnot institutes network brings together a large number of science and technology professionals, from sectors as varied as healthcare, ICT, mechanics, materials and processes, energy and chemistry. It combines scientific excellence with professionalism, using its skills to support and boost the innovation and competitiveness of companies of all sizes and ofsocio-economic actors.One of the main goals of the network is to be a source of wealth creation and job creation in France and in Europe.

Committed to partnership research development and as major players in the field of research, the Carnot institutes can mobilise all the skills of the network to meet companies’ research and innovation needs.

The Carnot institutes network is led by the “Association des instituts Carnot” (AiCarnot).

08 Feb