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Significant THz absorption in CH₃NH₂ molecular defect-incorporated organic-inorganic hybrid perovskite thin film.

ABSTRACT: The valid strong THz absorption at 1.58?THz was probed in the organic-inorganic hybrid perovskite thin film, CH₃NH₃PbI₃, fabricated by sequential vacuum evaporation method. In usual solution-based methods such as 2-step solution and antisolvent, we observed the relatively weak two main absorption peaks at 0.95 and 1.87?THz. The measured absorption spectrum is analyzed by density-functional theory calculations. The modes at 0.95 and 1.87?THz are assigned to the Pb-I vibrations of the inorganic components in the tetragonal phase. By contrast, the origin of the 1.58?THz absorption is due to the structural deformation of Pb-I bonding at the grain boundary incorporated with a CH₃NH₂ molecular defect.

SUBMITTER: Maeng I

PROVIDER: S-EPMC6456617 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Significant THz absorption in CH3NH2 molecular defect-incorporated organic-inorganic hybrid perovskite thin film.

Maeng Inhee I Lee Young Mi YM Park Jinwoo J Raga Sonia R SR Kang Chul C Kee Chul-Sik CS Yu Byung Deok BD Hong Suklyun S Ono Luis K LK Qi Yabing Y Jung Min-Cherl MC Nakamura Masakazu M

Scientific reports 20190409 1

The valid strong THz absorption at 1.58 THz was probed in the organic-inorganic hybrid perovskite thin film, CH3NH3PbI3, fabricated by sequential vacuum evaporation method. In usual solution-based methods such as 2-step solution and antisolvent, we observed the relatively weak two main absorption peaks at 0.95 and 1.87 THz. The measured absorption spectrum is analyzed by density-functional theory calculations. The modes at 0.95 and 1.87 THz are assigned to the Pb ...[more]

PMID: 30967593

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