SPLTRAK Abstract Submission
Potentiostatic Photoluminescence Imaging of Charge Extraction in Perovskite Solar Cells
Lukas Wagner1,2, Patrick Schygulla1,2, Jan Philipp Herterich1,3, Mohamed Elshamy1, Dmitry Bogachuk1,2, Salma Zouhair1,4, Simone Mastroianni1,3, Uli Würfel1,3, Yuhang Liu5, Shaik M. Zakeeruddin5, Michael Grätzel5, Andreas Hinsch1, Stefan W. Glunz1,2,3
1Fraunhofer Institute for Solar Energy Systems ISE, Freiburg, Germany
/2Laboratory for Photovoltaic Energy Conversion, University of Freiburg, Freiburg, Germany
/3Freiburg Materials Research Center FMF, University of Freiburg, Freiburg, Germany
/4Abdelmalek Essaadi University, Tangier, Morocco
/5Laboratory of Photonics and Interfaces (LPI), École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland

We propose a novel approach for microscopically resolved photocurrent imaging. The method is based on the notion that electrical bias-dependent photoluminescence images reveal fundamental information on charge extraction of photovoltaic devices. The approach is derived from basic physical principles and verified by means of a near-to-ideal III-V solar cell. It is demonstrated that the approach is of special relevance for liquid-processed perovskite solar cells. We outline the potential to investigate the local charge extraction efficiency, which can be related to fundamental charge extraction properties associated with the quality of interfaces and morphological defects from device processing. The method demonstrates that photoluminescence imaging can be a powerful tool for device optimization as well as fundamental studies when carried out at different bias voltages.