Alloying n-Butylamine into CsPbBr3 To Give a Two-Dimensional Bilayered Perovskite Ferroelectric Material

Zhenyue Wu; Chengmin Ji; Lina Li; Jintao Kong; Zhihua Sun; Sangen Zhao; Sasa Wang; Maochun Hong; Junhua Luo

doi:10.1002/anie.201803716

Alloying n-Butylamine into CsPbBr₃ To Give a Two-Dimensional Bilayered Perovskite Ferroelectric Material

Angew Chem Int Ed Engl. 2018 Jul 2;57(27):8140-8143. doi: 10.1002/anie.201803716. Epub 2018 May 25.

Authors

Zhenyue Wu^{1

2}, Chengmin Ji¹, Lina Li¹, Jintao Kong¹, Zhihua Sun¹, Sangen Zhao¹, Sasa Wang^{1

2}, Maochun Hong¹, Junhua Luo¹

Affiliations

¹ State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002, China.
² University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100039, P. R. China.

PMID: 29749686
DOI: 10.1002/anie.201803716

Abstract

Cesium-lead halide perovskites (e.g. CsPbBr₃ ) have gained attention because of their rich physical properties, but their bulk ferroelectricity remains unexplored. Herein, by alloying flexible organic cations into the cubic CsPbBr₃ , we design the first cesium-based two-dimensional (2D) perovskite ferroelectric material with both inorganic alkali metal and organic cations, (C₄ H₉ NH₃ )₂ CsPb₂ Br₇ (1). Strikingly, 1 shows a high Curie temperature (T_c =412 K) above that of BaTiO₃ (ca. 393 K) and notable spontaneous polarization (ca. 4.2 μC cm^-2 ), triggered by not only the ordering of organic cations but also atomic displacement of inorganic Cs⁺ ions. To our knowledge, such a 2D bilayered Cs⁺ -based metal-halide perovskite ferroelectric material with inorganic and organic cations is unprecedented. 1 also shows photoelectric semiconducting behavior with large "on/off" ratios of photoconductivity (>10³ ).

Keywords: CsPbBr3; ferroelectric materials; perovskites; phase transitions; two-dimensional materials.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, Non-U.S. Gov't