800.000 Euro for research on semitransparent solar cells and flexible OLEDs

Universities and company partners from Germany and Denmark present project on organic components at Hannover fair

Devices from organic materials such as solar cells (OPV), organic light emitting diodes (OLED) are characterized by mechanical flexibility, light weight, low costs, as well as semi-transparency. They could be used for solar cells as thin as foil, and so flexible that they can be integrated into large surfaces such as house or glass fronts. Possible applications are lighting, displays or photovoltaics, but also medical diagnostics. The RollFlex project has been rolling fast with development of these devices, while bridging to new industrial collaborations with local, regional, national and international partner setups. The positive developments have been noticed, and the EU Interreg 5A foundation has now acknowledged that by granting a fully funded extension of the project for another 18 months, supporting the project with 800.000 Euro. The extension project runs from April 2019 to September 2020, and while the main partners of University of Southern Denmark (SDU), Kiel University, Stensborg A/S and Phi-Stone AG remain the same, the number of network partners has now reached around 30 in total, and still growing. The partners of the project will present current insights of the fabrication and function of these organic devices at the booth of Kiel University at the Hannover Messe (hall 2, C07).

With their international research project “RollFlex” German and Danish scientists want to push the development of organic devices forward. The aim is to print organic material and devices on thin substrates such as flexible glass or plastic films. In the Danish town of Sønderborg a RollFlex Innovation Project Centre has been created as a laboratory for researching and developing roll-to-roll printing processes.

Top-emitting OLEDs

First a new OLED structure, based on the polymer "Super Yellow", has been analyzed on a laboratory scale: flexible and inverted top-emitting OLEDs were fabricated in the Kiel Nano Lab with the aim to be as efficient as inverted bottom-emitting OLEDs (8 cd/A). The top-emitting OLEDs are produced without Indium tin oxide. This way the processing costs are reduced and a roll-to-roll printing process is possible. Afterwards this new OLED structure had been upscaled at SDU in Sønderborg by slot-die coating. The efficiency of this OLEDs is indeed lower (2 cd/A), but they are the first top-emitting OLEDs fabricated this way that achieve 3000 cd/m².

Together with her team Martina Gerken, Professor at the Institute of Electrical Engineering and Information Technology and project leader at the CAU, also wants to create tailor-made light extraction of OLED via structuring the surface on a nano and microscale in wavelengths and output coupling angles. The working group works closely together with Phi-Stone AG to develop foils with special microparticles such as zinc oxide that protect organic light elements from outside effects and increase the scattering effect.

RollFlex bundles excellent competencies in the areas of roll-to-roll printing and optimization of organic components. With combined experience from industry and research we want to develop organic devices for the industrial market,” said Martina Gerken.

Semi-transparent and flexible solar modules fresh out of the print

In the RollFlex project, new flexible organic solar cell demonstrator modules have been developed from slot-die printing in the R2R facility at SDU in Sønderborg. The semi-transparent solar modules are developed from a non-fullerene based OPV system that can be printed in air, using only eco-friendly materials. Furthermore, the modules are free of the brittle and costly ITO material, otherwise used for the transparent electrodes. While the non-transparent printed solar cells reach efficiencies of around 5%, the semi-transparent module version currently show efficiencies of up to 3% - and still being developed further. The semi-transparent and flexible organic solar module is the second solar demonstrator coming out of the RollFlex innovation center, where the solar plant was demonstrated in 2018.

“We are very pleased about the progress shown in the RollFlex project, where we demonstrate new research and development outputs on R2R organic devices, as well as new industrial collaborations on this technology. We are grateful that Interreg has decided to support the project with another large grant,” said Associate Professor Morten Madsen, head of the OPV group at SDU NanoSYD in Sønderborg, and leader of the RollFlex project.

New imprint tool launched

Inspired by the work in the Rollflex network, Stensborg A/S has developed an imprint tool for students to ease their work in nanoimprint lithography. The HoloPrinter UNI A6 DT is the final result, and it is launched to the market this March as an easy-to-use desktop unit for lab-scale NIL work. Typical applications include imprinting of functional structures like lab-on-chip, diffractive optical elements and other types of nano-imprinted structures. The HoloPrinter Desktop also allows the user to do test and characterization of photo-curable resins and imprint materials.

About RollFlex:

The RollFlex Innovation Project Centre is being funded from 2016-2019 by the EU subsidy programme Interreg Deutschland-Danmark with around 1.6 million Euros, and is now extended with 0.8 million Euro running until September 2020. Partner institutions involved are the SDU, CAU, Phi-Stone GmbH and Stensborg A/S. There is also a multitude of network partners in northern Germany and Denmark.

CAU@Hannover Messe:

After 33 years, CEBIT and the Hannover Messe are joining forces. From 1 to 5 April, more than 6,000 exhibitors at the world's leading industrial trade show will present the latest developments in the fields of digitalization, Industry 4.0 and research. Kiel University (CAU) is among these for the third time. In Hall 2 "Research & Technology", scientists from the true north will present 17 interdisciplinary and transdisciplinary research projects. In addition, 39 stage presentations will offer an over-the-shoulder perspective of current research projects on topics such as battery research, autonomous ship navigation or radar-based pollutant measurement procedures. Joint panel discussions with the Schleswig-Holstein Ministry of Education and Ministry of Economics, a parliamentary evening, and hands-on activities and experiments with the Kieler Forschungswerkstatt (Kiel Research Workshop) round off the offerings. Details can be found at www.uni-kiel.de/hannovermesse


Prof. Dr. Martina Gerken
Kiel University
Institute of Electrical Engineering and Information Technology
Integrated Systems and Photonics
+49 431 880 6250

Dr. Ala Cojocaru
Project leader Phi-Stone AG
+49 431 7054186

Associate Prof. Morten Madsen
OPV group leader, RollFlex project leader
University of Southern Denmark
SDU NanoSYD, Mads Clausen Institute
Alsion 2, 6400 Sønderborg
+45 6550 1621

Stensborg A/S
+45 4677 5930

Press contact:

Julia Siekmann
Science communication
Priority research area Kiel Nano, Surface and Interface Science (KiNSIS)

About the priority research area KiNSIS:

Details, which are only a millionth of a millimetre in size: this is what the priority research area "Kiel Nano, Surface and Interface Science – KiNSIS" at Kiel University has been working on. In the nano-cosmos, different laws prevail than in the macroscopic world - those of quantum physics. Through intensive, interdisciplinary cooperation between physics, chemistry, engineering and life sciences, the priority research area aims to understand the systems in this dimension and to implement the findings in an application-oriented manner. Molecular machines, innovative sensors, bionic materials, quantum computers, advanced therapies and much more could be the result. More information at www.kinsis.uni-kiel.de



You can find the CAU booth in hall 2 directly through the north entrance. If you arrive by car, the Messe Nord parking lots are the nearest.

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