Light-Induced Structural Dynamics and Charge Transport in Layered Halide Perovskite Thin Films

Tsai, Hsinhan; Ghosh, Dibyajyoti; Kinigstein, Eli; Dryzhakov, Bogdan; Driscoll, Honora; Owczarek, Magdalena; Hu, Bin; Zhang, Xiaoyi; Tretiak, Sergei; Nie, Wanyi

doi:10.1021/acs.nanolett.2c03403

DOE OSTI · 1909561

Light-Induced Structural Dynamics and Charge Transport in Layered Halide Perovskite Thin Films

Tsai, Hsinhan·Ghosh, Dibyajyoti·Kinigstein, Eli·Dryzhakov, Bogdan·Driscoll, Honora·Owczarek, Magdalena·Hu, Bin·Zhang, Xiaoyi·Tretiak, Sergei·Nie, Wanyi

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Abstract

The dynamic nature of the metal halide perovskite lattice upon photoexcitation plays a vital role in their properties. Here we report an observation of light-induced structure dynamics in quasi-2D Ruddlesden–Popper phase perovskite thin films and its impact on the carrier transport properties. By a time-resolved X-ray scattering technique, we observe a rapid lattice expansion upon photoexcitation, followed by a slow relaxation over the course of 100 ns in the dark. Theoretical modeling suggests that the expansion originates from the lattice’s thermal fluctuations caused by photon energy deposition. Power dependent optical spectroscopy and photoconductivity indicate that high laser powers triggered a strong local structural disorder, which increased the charge dissociation activation energy that results in localized transport. Finally, our study investigates the impact of laser energy deposition on the lattices and the subsequent carrier transport properties, that are relevant to device operations.

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2D perovskites 36 MATERIALS SCIENCE charge transport structural dynamics thin film

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Tsai, Hsinhan, Ghosh, Dibyajyoti, Kinigstein, Eli, Dryzhakov, Bogdan, Driscoll, Honora, Owczarek, Magdalena, Hu, Bin, Zhang, Xiaoyi, Tretiak, Sergei, Nie, Wanyi. 2023-01-05. Light-Induced Structural Dynamics and Charge Transport in Layered Halide Perovskite Thin Films. https://doi.org/10.1021/acs.nanolett.2c03403

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