Zhang Weichuan, Hong Maochun, Luo Junhua
CAS Key Laboratory of Nanosystem and Hierachical Fabrication CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, People's Republic of China.
State Key Laboratory of Structure Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou, Fujian, 350002, People's Republic of China.
J Am Chem Soc. 2021 Oct 13;143(40):16758-16767. doi: 10.1021/jacs.1c08281. Epub 2021 Oct 4.
Linear dichroic anisotropic photonic materials are highly attractive due to their great potentials in many applications, which in combination with the ferroelectric properties could broaden their research and applications. However, to date, the linear dichroism conversion phenomenon has not been observed in one-dimensional (1D) large-size single-crystal materials: in particular, lead-free perovskite ferroelectric crystals. Here, we propose a new ferroelectric design strategy: namely, partial organic cation substitution for precisely designing 1D polarization-sensitive perovskite ferroelectrics. As an example, the 1D mixed-cation perovskite ferroelectric (-propylammonium)(methylammonium)SbBr was synthesized, which exhibits a fascinating ferroelectricity with a notable reversible polarization of 2.9 μC/cm and a large ferroelectricity-driven polarization ratio of 6.9. Importantly, the single-crystalline photodetectors also exhibit superior optoelectronic anisotropic performances at the paraelectric phase, having a large photoelectric anisotropy ratio (∼35), an excellent polarization-sensitive dichroism ratio (∼1.31), highly sensitive detectivity up to ∼10 Jones, and a fast response rate (∼45/68 μs). This finding provides a significant and effective pathway for the targeted design of new functional lead-free linear dichroic anisotropic photonic ferroelectrics.
线性二向色性各向异性光子材料因其在许多应用中具有巨大潜力而极具吸引力，若将其与铁电特性相结合，可拓宽其研究和应用范围。然而，迄今为止，在一维（1D）大尺寸单晶材料中尚未观察到线性二向色性转换现象，特别是无铅钙钛矿铁电晶体。在此，我们提出一种新的铁电设计策略：即通过部分有机阳离子取代来精确设计一维偏振敏感钙钛矿铁电体。例如，合成了一维混合阳离子钙钛矿铁电体（-丙基铵）（甲基铵）SbBr，它表现出迷人的铁电性，具有2.9 μC/cm的显著可逆极化和6.9的大铁电驱动极化率。重要的是，单晶光电探测器在顺电相也表现出优异的光电各向异性性能，具有大的光电各向异性比（约35）、出色的偏振敏感二向色性比（约1.31）、高达约10琼斯的高灵敏度探测率以及快速响应速率（约45/68 μs）。这一发现为新型功能性无铅线性二向色性各向异性光子铁电体的靶向设计提供了一条重要且有效的途径。
