Transport resistance dominates the fill factor losses in record organic solar cells

作     者：Wang, Chen MacKenzie, Roderick C.I. Würfel, Uli Neher, Dieter Kirchartz, Thomas Deibel, Carsten Saladina, Maria 

作者机构：Institut für Physik Technische Universität Chemnitz Chemnitz09126 Germany Department of Engineering Durham University Lower Mount Joy South Road DurhamDH1 3LE United Kingdom Fraunhofer Institute for Solar Energy Systems ISE Heidenhofstr. 2 Freiburg79110 Germany Freiburg Materials Research Center FMF University of Freiburg Stefan-Meier-Str. 21 Freiburg79104 Germany Institute of Physics and Astronomy University of Potsdam Karl-Liebknecht-Str.24-25 Potsdam-GolmD-14476 Germany IMD-3 Photovoltaik Forschungszentrum Jülich Jülich52425 Germany Faculty of Engineering CENIDE University of Duisburg-Essen Carl-Benz-Str. 199 Duisburg47057 Germany 

出 版 物：《arXiv》 (arXiv)

年 卷 期：2024年

核心收录：

主　　题：Organic solar cells 

摘      要：Organic photovoltaics are a promising solar cell technology well-suited to mass production using roll-to-roll processes. The efficiency of lab-scale solar cells has exceeded 20% and considerable attention is currently being given to understanding and minimising the remaining loss mechanisms preventing higher efficiencies. While recent efficiency improvements are partly owed to reducing non-radiative recombination losses at open-circuit, the low fill factor due to a significant transport resistance is becoming the Achilles heel of organic photovoltaics. The term transport resistance refers to a voltage and light intensity dependent charge collection loss in low-mobility materials. In this Perspective, we demonstrate that even the highest efficiency organic solar cells reported to-date have significant performance losses that can be attributed to transport resistance and that lead to high fill factor losses. We provide a closer look at the transport resistance and the material properties influencing it. We describe how to experimentally characterise and quantify the transport resistance by providing easy to follow instructions. Furthermore, the causes and theory behind transport resistance are detailed. In particular, we integrate the relevant figures of merit and different viewpoints on the transport resistance. Finally, we outline strategies that can be followed to minimise these charge collection losses in future solar cells. Copyright © 2024, The Authors. All rights reserved.