Perovskite oxides such as PbZr_xTi_1−xO₃ (PZT) and BaTiO₃ show excellent dielectric, piezoelectric, pyroelectric, and ferroelectric properties simultaneously and have been widely used in capacitor, sensor, actuator, motor, surface acoustic wave devices, and energy storage applications. Recently, a variety of solution‐processed halide perovskite materials have been discovered to exhibit fascinating properties such as high charge mobility, strong light absorption, and even ferroelectricity. In this review, the recent progress on two classes of halide perovskite ferroelectrics is summarized. The first class is organo‐lead halide perovskite semiconductor such as MAPbI₃ (MA=CH₃NH₃⁺), which is intensively pursued for solar cell and light emitting diode applications. Dynamic ferroelectric polarization is believed to be one of the essential factors to protect carriers from being scattered by charged defects in these halide perovskites. The second class is normal/multilayered halide perovskite ferroelectrics with large polarization or strong piezoelectricity. The piezoelectric coefficient of these latter perovskites can be as high as ≈1540 pC N⁻¹, comparable to those of PZT‐based ferroelectrics. Multiaxial polarizations and morphotropic phase boundaries are also demonstrated in such halide perovskites. Overall, the fast development of halide perovskite ferroelectrics opens a new avenue for not only advancing fundamental materials science but also designing novel electronic and photoelectric devices.

中文翻译：

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卤化物钙钛矿中铁电的出现

PbZr _x Ti _{1- x} O ₃（PZT）和BaTiO ₃等钙钛矿氧化物同时显示出优异的介电，压电，热电和铁电性能，并已广泛用于电容器，传感器，致动器，电机，表面声波器件和储能应用。近年来，已发现各种溶液处理的卤化钙钛矿材料具有令人着迷的特性，例如高电荷迁移率，强光吸收性甚至铁电性。在这篇综述中，总结了两类卤化钙钛矿铁电体的最新进展。第一类是有机铅卤化钙钛矿半导体，例如MAPbI ₃（MA = CH ₃NH ₃ ⁺），在太阳能电池和发光二极管应用中被广泛使用。动态铁电极化被认为是保护载流子免受这些卤化物钙钛矿中带电缺陷驱散的重要因素之一。第二类是具有大极化或强压电性的普通/多层卤化物钙钛矿铁电体。这些后钙钛矿的压电系数可以高达≈1540pC N ^-1，与基于PZT的铁电材料相当。在这种卤化物钙钛矿中也证明了多轴极化和同相相界。总体而言，卤化物钙钛矿铁电材料的快速发展不仅为推进基础材料科学而且为设计新颖的电子和光电器件开辟了一条新途径。