MAPbI₃ is deemed as the most prominent member in hybrid perovskites family because of its extremely optoelectronic properties. However, some issues and puzzles are still in expectation of their answers, such as stabilities, hysteresis, ferroelectricity, and so on. To bridge the distinctions between MAPbI₃ single crystal and thin films, large-size single crystals are demanded. On the contrary, crystal structure anisotropy-dependent optoelectronic properties is an inevitable topic. A series of large-size MAPbI₃ single crystals with (220) facets exposed were successfully grown, using high concentration solutions and large-size seed crystals to match growth rates of (100) and (220) facets. The optoelectronic properties of photocurrents, responsivity, EQE, and detectivity clearly showed significant anisotropy of optoelectronic properties in MAPbI₃ single crystal. According to ion migration theory, the anisotropy of optoelectronic properties was interpreted. We hope this result will be helpful to guide oriented growth MAPbI₃ thin films.

中文翻译：

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露出（220）面的MAPbI ₃单晶的设计生长及其优异的光电性能

MAPbI ₃由于具有极高的光电特性，因此被认为是钙钛矿杂化家族中最重要的成员。但是，仍然需要一些问题和困惑，例如稳定性，磁滞，铁电性等等。为了弥合MAPbI ₃单晶和薄膜之间的区别，需要大尺寸的单晶。相反，依赖于晶体结构的各向异性的光电特性是不可避免的话题​​。一系列大型MAPbI ₃使用高浓度溶液和大尺寸种子晶体成功地生长了暴露（220）面的单晶，以匹配（100）和（220）面的生长速率。在MAPbI ₃单晶中，光电流，响应度，EQE和探测性的光电性质明显显示出显着的各向异性。根据离子迁移理论，解释了光电特性的各向异性。我们希望这一结果将有助于指导定向生长MAPbI ₃薄膜。