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Updated: Jul 9, 2025

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity
Published on: March 6, 2017
Spatio-Temporal Dynamics of Free and Bound Carriers in Photovoltaic Materials
George Fish1, Jacques-E Moser2
1Group for Photochemical Dynamics, Institute of Chemical Science and Engineering, École polytechnique fédérale de Lausanne, EPFL SB ISIC GR-MO, Station 6, CH-1015 Lausanne. george.fish@epfl.ch.
Abstract:
Charge transfer and subsequent separation into free carriers are key processes that govern the efficiencies of third generation solar cell technologies based on donor-acceptor heterojunctions. As these processes typically occur on picosecond to femtosecond timescales, it is necessary to employ ultrafast spectroscopic techniques to further our understanding of these processes in order to provide vital information that can aide in furthering material design. Within the framework of the National Centre of Competence in Research "Molecular Ultrafast Science and Technology" (NCCR MUST), we have developed and utilized a suite of different ultrafast spectroscopic techniques to study charge generation, separation and recombination in a variety of small molecule based organic solar cells and lead halide perovskites. Here, we provide an overview of the main techniques used in our laboratory and the recent results obtained using these spectroscopic techniques.
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