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Heterogeneous Supersaturation in Mixed Perovskites.

ABSTRACT: Thin-film solar cells based on hybrid lead halide perovskites have achieved certified power conversion efficiencies exceeding 24%, approaching those of crystalline silicon. This motivates deeper studies of the mechanisms that determine their performance. Twin defect sites have been proposed as a source of traps in perovskites, yet their origin and influence on photovoltaic performance remain unclear. It is found that twin defects-observed herein via both transmission electron microscopy and X-ray diffraction-are correlated with the amount of antisolvent added to the perovskite and that twin defects in the highest-performing perovskite photovoltaics are suppressed. Heterogeneous supersaturation nucleation is discussed as a contributor to efficient perovskite-based optoelectronic devices.

SUBMITTER: Tan CS

PROVIDER: S-EPMC7140989 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Heterogeneous Supersaturation in Mixed Perovskites.

Tan Chih Shan CS Hou Yi Y Saidaminov Makhsud I MI Proppe Andrew A Huang Yu Sheng YS Zhao Yicheng Y Wei Mingyang M Walters Grant G Wang Ziyun Z Zhao Yongbiao Y Todorovic Petar P Kelley Shana O SO Chen Lih Juann LJ Sargent Edward H EH

Advanced science (Weinheim, Baden-Wurttemberg, Germany) 20200208 7

Thin-film solar cells based on hybrid lead halide perovskites have achieved certified power conversion efficiencies exceeding 24%, approaching those of crystalline silicon. This motivates deeper studies of the mechanisms that determine their performance. Twin defect sites have been proposed as a source of traps in perovskites, yet their origin and influence on photovoltaic performance remain unclear. It is found that twin defects-observed herein via both transmission electron microscopy and X-ra ...[more]

PMID: 32274311

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