Roar Søndergaard

Mr. Roar Søndergaard


Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2012 in Materials Today
Verified
Journal Article
Open access
RSRoar Søndergaard
Roar Søndergaard
MHMarkus Hösel
Markus Hösel
DADechan Angmo
Dechan Angmo
TLThue T. Larsen-Olsen
Thue T. Larsen-Olsen
FKFrederik Krebs
Frederik Krebs

19 October 2012 in Journal of Polymer Science Part B: Polymer Physics
Verified
Journal Article
Open access
PDF file
RSRoar Søndergaard
Roar Søndergaard
MHMarkus Hösel
Markus Hösel
FKFrederik Krebs
Frederik Krebs
With the prospect of extremely fast manufacture of very low cost devices, organic electronics prepared by thin film processing techniques that are compatible with roll‐to‐roll (R2R) methods are presently receiving an increasing interest. Several technologies using organic thin films are at the point, where transfer from the laboratory to a more production‐oriented environment is within reach. In this review, we aim at giving an overview of some of the R2R‐compatible techniques that can be used in such a transfer, as well the current status of R2R application within some of the existing research fields such as organic photovoltaics, organic thin film transistors, light‐emitting diodes, polymer electrolyte membrane fuel cells, and electrochromic devices. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

8 October 2013 in Advanced Materials
Verified
Journal Article
Closed access
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FKFrederik Krebs
Frederik Krebs
NENieves Espinosa
Nieves Espinosa
MHMarkus Hösel
Markus Hösel
RSRoar Søndergaard
Roar Søndergaard
MJMikkel Jørgensen
Mikkel Jørgensen

14 October 2009 in Journal of Materials Chemistry
Verified
Journal Article
Closed access
PDF file
MHMartin Helgesen
Martin Helgesen
RSRoar Søndergaard
Roar Søndergaard
FKFrederik Krebs
Frederik Krebs
The rapidly expanding field of polymer and organic solar cells is reviewed in the context of materials, processes and devices that significantly deviate from the standard approach which involves rigid glass substrates, indium-tin-oxide electrodes, spincoated layers of conjugated polymer/fullerene mixtures and evaporated metal electrodes in a flat multilayer geometry. It is likely that significant advances can be found by pursuing many of these novel ideas further and the purpose of this review is to highlight these reports and hopefully spark new interest in materials and methods that may be performing less than the current state-of-the-art in their present form but that may have the potential to outperform these pending a larger investment in effort.

19 June 2014 in Energy & Environmental Science
Verified
Journal Article
Closed access
PDF file
TAThomas R. Andersen
Thomas R. Andersen
HDHenrik F. Dam
Henrik F. Dam
MHMarkus Hösel
Markus Hösel
MHMartin Helgesen
Martin Helgesen
JCJon E. Carlé
Jon E. Carlé
FKFrederik Krebs
Frederik Krebs
Inline printing and coating methods have been demonstrated to enable a high technical yield of fully roll-to-roll processed polymer tandem solar cell modules. We demonstrate generality by employing different material sets and also describe how the ink systems must be carefully co-developed in order to reach the ambitious objective of a fully printed and coated 14-layer flexible tandem solar cell stack. The roll-to-roll methodologies involved are flexographic printing, rotary screen printing, slot-die coating, X-ray scattering, electrical testing and UV-lamination. Their combination enables the manufacture of completely functional devices in exceptionally high yields. Critical to the ink and process development is a carefully chosen technology transfer to industry method where first a roll coater is employed enabling contactless stack build up, followed by a small roll-to-roll coater fitted to an X-ray machine enabling in situ studies of wet ink deposition and drying mechanisms, ultimately elucidating how a robust inline processed recombination layer is key to a high technical yield. Finally, the transfer to full roll-to-roll processing is demonstrated.

4 February 2011 in Journal of Materials Chemistry
Verified
Journal Article
Closed access
PDF file
MMMatthieu Manceau
Matthieu Manceau
EBEva Bundgaard
Eva Bundgaard
JCJon E. Carlé
Jon E. Carlé
OHOle Hagemann
Ole Hagemann
MHMartin Helgesen
Martin Helgesen
FKFrederik Krebs
Frederik Krebs
A comparative photochemical stability study of a wide range of π-conjugated polymers relevant to polymer solar cells is presented. The behavior of each material has been investigated under simulated sunlight (1 sun, 1000 W m−2, AM 1.5G) and ambient atmosphere. Degradation was monitored during ageing combining UV-visible and infrared spectroscopies. From the comparison of the collected data, the influence of the polymer chemical structure on its stability has been discussed. General rules relative to the polymer structure–stability relationship are proposed.