Su Chang-Yuan, Yao Ye-Feng, Zhang Zhi-Xu, Wang Ying, Chen Ming, Huang Pei-Zhi, Zhang Yi, Qiao Wen-Cheng, Fu Da-Wei
Ordered Matter Science Research Center, Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University Nanjing 211189 China
Institute for Science and Applications of Molecular Ferroelectrics, Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Zhejiang Normal University Jinhua 321004 China
Chem Sci. 2022 Mar 30;13(17):4794-4800. doi: 10.1039/d1sc07045b. eCollection 2022 May 4.
Two-dimensional (2D) hybrid double perovskites have attracted extensive research interest for their fascinating physical properties, such as ferroelectricity, X-ray detection, light response and so on. In addition, ferroelastics, as an important branch of ferroic materials, exhibits wide prospects in mechanical switches, shape memory and templating electronic nanostructures. Here, we designed a 2D phase-transition double perovskite ferroelastic through a structurally progressive strategy. This evolution is core to our construction process from 0D to 1D and AgBi-based 2D. In this way, we successfully synthesized 2D lead-free ferroelastic (DPA)AgBiBr (DPA = 2,2-dimethylpropan-1-aminium) with a high Curie temperature ( ), which shows a narrower band gap than 0D (DPA)BiBr and 1D (DPA)PbBr. Moreover, the mechanism of structural phase transition and molecular motion are fully characterized by temperature dependent solid-state NMR and single crystal XRD. (DPA)AgBiBr injects power into the discovery of new ferroelastics or the construction and dimensional adjustment in new hybrid double perovskites.
二维（2D）杂化双钙钛矿因其迷人的物理性质，如铁电性、X射线探测、光响应等，而吸引了广泛的研究兴趣。此外，铁弹性体作为铁电材料的一个重要分支，在机械开关、形状记忆和模板化电子纳米结构方面展现出广阔的前景。在此，我们通过一种结构递进策略设计了一种二维相变双钙钛矿铁弹性体。这种演化是我们从0D到1D以及基于AgBi的2D构建过程的核心。通过这种方式，我们成功合成了具有高居里温度（ ）的二维无铅铁弹性体（DPA）AgBiBr（DPA = 2,2-二甲基丙-1-铵），其带隙比0D（DPA）BiBr和1D（DPA）PbBr更窄。此外，通过变温固态核磁共振和单晶X射线衍射对结构相变和分子运动的机制进行了充分表征。（DPA）AgBiBr为新型铁弹性体的发现或新型杂化双钙钛矿的构建及维度调整注入了动力。
