at Google ScholarTitle data
Witt, Christina ; Leupold, Nico ; Ramming, Philipp ; Schötz, Konstantin ; Moos, Ralf ; Panzer, Fabian:
How the Microstructure of MAPbI₃ Powder Impacts Pressure-Induced Compaction and Optoelectronic Thick-Film Properties.
In: The Journal of Physical Chemistry C.
Vol. 126
(2022)
Issue 36
.
- pp. 15424-15435.
ISSN 1932-7455
DOI: https://doi.org/10.1021/acs.jpcc.2c03329
Project information
| Project title: |
Project's official title Project's id Stabile Perowskitsolarzellen durch kontrollierte Kristallisationsprozesse und durch grundlegendes Verständnis der optischen und elektrischen Eigenschaften sowie der Defektchemie MO 1060/32-1 No information PA 3373/3 |
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Abstract in another language
Within the last few years, applying pressure to improve and alter the structural and optoelectronic properties of halide perovskite thin films and powder-based thick-film pellets has emerged as a promising processing method. However, a detailed understanding of the relationship between perovskite microstructure, pressing process, and final film properties is still missing. Here, we investigate the impact of powder microstructure on the compaction processes during pressure treatment and on the final properties of powder-pressed thick films, using the model halide perovskite methylammonium lead iodide (MAPbI3). Analyzing pressure relaxations together with XRD and SEM characterizations, we find that larger powder particles result in less compact thick films with higher surface roughness. Furthermore, larger particles exhibit stronger sintered connections between individual powder particles, resulting in less crushing and particle rearrangement but in more pronounced plastic deformation during pressure treatment. Moreover, plastic deformation of the powder particles leads to a reduction of crystallite size in the final film. This reduction results in increased nonradiative, defect-associated excited state recombination, as confirmed by photoluminescence investigations. More plastic deformation also deteriorates the grain boundary quality and consequently facilitates ion migration, which is reflected in higher electrical dark conductivities of the thick films. Thus, our work elucidates how important the design of the perovskite powder microstructure is for the pressure-induced compaction behavior and for the resulting structural, optical, and electrical thick-film properties. These insights will pave the way for tailored pressure processing of halide perovskite films with improved optoelectronic properties.