Berlin 2024 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 88: Focus Session: Ultrafast Processes in Organic Semiconductors and Perovskites II (joint session O/CPP)

O 88.7: Vortrag

Donnerstag, 21. März 2024, 16:45–17:00, MA 004

Self-Trapped Exciton Emission in Two Families of Antimony and Bismuth Halide Perovskites — •Lukas Gümbel¹, Philip Klement¹, Meng Yang², Sangam Chatterjee¹, and Johanna Heine² — ¹Institute of Experimental Physics I and Center for Materials Research, JLU Gießen, Germany — ²Department of Chemistry and Material Sciences Centre, PU Marburg, Germany

Main group metal halide materials are currently explored for a variety of applications including solar cells, but also light emitting devices (LED), lasers, sensing, and photo-catalysis. They promiss less harmful alternatives to the prominent lead halide perovskites. This study investigates the optical properties of antimony and bismuth halide compounds. Temperature-dependent photoluminescence spectroscopy reveals the electron-phonon coupling andyields a Huang-Rhys factor in trhe range of 5 to 22. The broad emission bands and large Stokes shifts suggest self-trapped exciton (STE) emission, linked to an interaction between the photogenerated electron-hole pairs and the lattice. The intricate interplay of factors like ground and excited state distortion, lattice softness, and electron-phonon coupling necessitates deeper understanding. A systematic analysis contributes to establishing the general structure-property relationships for STE emission in such metal halide perovskite-derivate materials. Additionally, the study delves into the diffusion of self-trapped excitons through temporal and spatial resolved photoluminescence, enhancing comprehension of emission processes.

Keywords: Perovskites; Diffusion Dynamics; Self-Trapped Exciton; Photoluminescence