Regensburg 2019 – wissenschaftliches Programm
AKjDPG 1: PhD Focus Session: Photoluminescence of halide perovskites: What does it tell us and what not? (joint session DS/HL/AKjDPG)
AKjDPG 1.7: Hauptvortrag
Dienstag, 2. April 2019, 12:00–12:30, H32
Photophysics of Sn-based hybrid perovskites — •Maria Antonietta Loi — Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands
Thanks to the intensive research efforts of a large scientific community over the past years, lead (Pb)-based hybrid perovskite solar cells have reached impressive (>23%) power conversion efficiency. Against the initial criticism about their instability, also large improvements in the thermal and photo stability of this kind of solar cells were obtained in the last years. Despite these outstanding accomplishments, the toxicity of lead causes concerns about the possible large-scale utilization of this new type of solar cell. Among the various alternatives to lead, Sn has been recognized to have a great potential, as the Sn-based hybrid perovskites display excellent optical and electrical properties such as high absorption coefficients, very small exciton binding energies and high charge carrier mobilities. Recently solar cells with efficiencies approaching 10% have been reported. In my presentation I will report about important features of the photophysical properties of formamidinium tin triiodide. Photoluminescence spectra are highly assimetric at the high-energy edge. This is accompanied by the unusually large blue shift of the time-integrated photoluminescence with increasing of the excitation power. These phenomena are associated with very slow hot carrier relaxation and state-filling of band edge states. Most importantly, the hot carrier photoluminescence is evident not only upon pulsed excitation but also with continuous wave one.