气候变化领域集成服务门户(CCPortal): Tetragonal CH3NH3Pbi3 is ferroelectric

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DOI	10.1073/pnas.1702429114
	Tetragonal CH3NH3Pbi3 is ferroelectric
	Rakita Y.; Bar-Elli O.; Meirzadeh E.; Kaslasi H.; Peleg Y.; Hodes G.; Lubomirsky I.; Oron D.; Ehre D.; Cahen D.
发表日期	2017
ISSN	0027-8424
起始页码	E5504
结束页码	E5512
卷号	114 期号:28
英文摘要	Halide perovskite (HaP) semiconductors are revolutionizing photovoltaic (PV) solar energy conversion by showing remarkable performance of solar cells made with HaPs, especially tetragonal methylammonium lead triiodide (MAPbI3). In particular, the low voltage loss of these cells implies a remarkably low recombination rate of photogenerated carriers. It was suggested that low recombination can be due to the spatial separation of electrons and holes, a possibility if MAPbI3 is a semiconducting ferroelectric, which, however, requires clear experimental evidence. As a first step, we show that, in operando, MAPbI3 (unlike MAPbBr3) is pyroelectric, which implies it can be ferroelectric. The next step, proving it is (not) ferroelectric, is challenging, because of the material's relatively high electrical conductance (a consequence of an optical band gap suitable for PV conversion) and low stability under high applied bias voltage. This excludes normal measurements of a ferroelectric hysteresis loop, to prove ferroelectricity's hallmark switchable polarization. By adopting an approach suitable for electrically leaky materials as MAPbI3, we show here ferroelectric hysteresis from well-characterized single crystals at low temperature (still within the tetragonal phase, which is stable at room temperature). By chemical etching, we also can image the structural fingerprint for ferroelectricity, polar domains, periodically stacked along the polar axis of the crystal, which, as predicted by theory, scale with the overall crystal size. We also succeeded in detecting clear second harmonic generation, direct evidence for the material's noncentrosymmetry. We note that thematerial's ferroelectric nature, can, but need not be important in a PV cell at room temperature.
英文关键词	Ferroelectricity; Halide perovskites; Photovoltaics; Pyroelectricity; Semiconductors
语种	英语
scopus关键词	methylammonium; perovskite; Article; crystal; electric conductance; electric potential; hysteresis; low temperature; polarization; priority journal; room temperature; semiconductor
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160615
作者单位	Rakita, Y., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Bar-Elli, O., Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot, 7610001, Israel; Meirzadeh, E., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Kaslasi, H., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Peleg, Y., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Hodes, G., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Lubomirsky, I., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Oron, D., Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot, 7610001, Israel; Ehre, D., Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot, 7610001, Israel; Cahen, D., Department of Materi...
推荐引用方式 GB/T 7714	Rakita Y.,Bar-Elli O.,Meirzadeh E.,et al. Tetragonal CH3NH3Pbi3 is ferroelectric[J],2017,114(28).
APA	Rakita Y..,Bar-Elli O..,Meirzadeh E..,Kaslasi H..,Peleg Y..,...&Cahen D..(2017).Tetragonal CH3NH3Pbi3 is ferroelectric.Proceedings of the National Academy of Sciences of the United States of America,114(28).
MLA	Rakita Y.,et al."Tetragonal CH3NH3Pbi3 is ferroelectric".Proceedings of the National Academy of Sciences of the United States of America 114.28(2017).