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 1.6: Vortrag
Dienstag, 2. April 2019, 11:45–12:00, H32
Temperature dependent charge carrier transport in MAPI single crystal thin films — •Alexander Biewald1, Richard Ciesielski1, Nadja Giesbrecht1, Kathrin Handloser1, Pablo Docampo2, Thomas Bein1, and Achim Hartschuh1 — 1Department Chemie und (CeNS), LMU München, Deutschland — 2School of Electrical and Electronic Engineering, Newcastle, UK
Methylammonium lead iodide (MAPI)-based thin-film solar cells today reach power conversion efficiencies of more than 20 % . The material is prototypical for the large class of perovskite semiconductor materials for photovoltaic applications and is therefore at the focal point of research interest to a global community. Here, we present an all-optical study of the charge carrier diffusion properties in large-crystal MAPI thin films using photoluminescence microscopy . We vary the temperature between 170 K and room temperature, thus remaining in the tetragonal crystal phase . We probe the local material properties of individual crystal grains within a PMMA-coated MAPI thin film and find a steady increase of the diffusion constant towards lower temperatures. In a previous paper we found that grain boundaries in such thin films act as solid walls for diffusing charge carriers , which we also see at low temperatures.
 M. A. Green, et al., Solar cell efficiency tables (version 52), 2018.
 R. Ciesielski, et al., ACS Appl. Mat. & Interfaces. 10 (9), 7974-7981 (2018).
 N.O. Yamamuro, et al., J. Phys. Chem. Solids 53 (7), 935-939 (1992).