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Updated: Jul 3, 2025
Influence of Hybrid Perovskite Fabrication Methods on Film Formation, Electronic Structure, and Solar Cell Performance
Published on: February 27, 2017
Effect of Single-Crystal TiO2/Perovskite Band Alignment on the Kinetics of Electron Extraction
Xiangtian Chen1, Hannu P Pasanen2, Ramsha Khan2
1Department of Physical Chemistry and Materials Science, Interdisciplinary Excellence Centre, University of Szeged, Aradi Square 1, Szeged H-6720, Hungary.
Abstract:
The kinetics of electron extraction at the electron transfer layer/perovskite interface strongly affects the efficiency of a perovskite solar cell. By combining transient absorption and time-resolved photoluminescence spectroscopy, the electron extraction process between FA0.83Cs0.17Pb(I0.83Br0.17)3 and TiO2 single crystals with different orientations of (100), (110), and (111) were probed from subpicosecond to several hundred nanoseconds. It was revealed that the band alignment between the constituents influenced the relative electron extraction process. TiO2(100) showed the fastest overall and hot electron transfer, owing to the largest conduction band and Fermi level offset compared to FA0.83Cs0.17Pb(I0.83Br0.17)3. It was found that an early electron accumulation in these systems can have an influence on the following electron extraction on the several nanosecond time scale. Furthermore, the existence of a potential barrier at the TiO2/perovskite interface was also revealed by performing excitation fluence-dependent measurements.
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