In the latest issue of Materials Today, Dr. Gilles Dennler of Konarka Austria GmbH and twenty other experts warn that a race to report organic solar cells (OSCs) with world record efficiencies is leading to a significant number of published papers claiming unrealistic and scientifically questionable results and performances.
“World record efficiencies are popping up almost every month, leading the OSC community into an endless and dangerous tendency to outbid the last report,” stated Dennler et al. in the article. “The current outbidding phenomenon does a severe disservice to the whole community, damaging its reputation. Solar cells and especially OSCs face enough difficulties in convincing people of their benefit over other energy sources.”
OSCs are potentially cheap and easy to fabricate. This makes them very attractive in comparison to the familiar silicon solar cells, which struggle to compete in cost with other energy sources. While its promise means the field is growing, OSCs still show relatively low efficiencies that will need to improve significantly before they become a success.
Dennler and colleagues urge the field to press for independent verification of solar cell efficiencies. They call on researchers to question their results and constantly push the accuracy of their findings and ask journal editors to review claims of significant advances thoroughly.
“In essence, this should be a good thing. Increasing the number of people focused on this tremendous renewable will hopefully help solve the planet’s energy needs,” adds Dennler. “Unfortunately, OSCs currently suffer from their own success.”
The increasing number of researchers and choice of where to publish results means that everyone is finding it increasingly difficult to gain an impact within the community. The result is a pursuit of eye-catching claims of solar cell efficiencies.
The signatories to this article are:
T. Ameri, P. Denk, H.-J. Egelhaaf, K. Forberich, M. Koppe, M. Morana, M. C. Scharber, C. Waldauf, Konarka Austria GmbH, Austria - these signatories state that their opinions do not represent those of Konarka Austria GmbH.
B. de Boer, University of Groningen, The Netherlands
K. Emery, G. Rumbles, National Renewable Energy Laboratory, USA
J. M. Kroon, Solar Energy – Energy Research Center of the Netherlands, The Netherlands
G. G. Malliaras, Cornell University, USA
M. D. McGehee, Stanford University, USA
J. Nelson, Imperial College, London, UK
M. Niggemann, Fraunhofer Institute for Solar Energy Systems, Germany
M. Pfeiffer, Heliatek GmbH, Germany
M. K. Riede, Institut für Angewandte Photophysik, Germany
S. E. Shaheen, University of Colorado, Denver, USA
M. Wienk, University of Technology, Eindhoven, The Netherlands.