An Lian-Cai, Li Kai, Li Zhi-Gang, Zhu Shengli, Li Qite, Zhang Zhuo-Zhen, Ji Li-Jun, Li Wei, Bu Xian-He
School of Materials Science and Engineering, TKL of Metal and Molecule Based Material Chemistry, Nankai University, Tianjin, 300350, China.
School of Materials Science and Engineering, Tianjin University, Tianjin, 300350, China.
Small. 2021 Jun;17(22):e2006021. doi: 10.1002/smll.202006021. Epub 2021 Mar 14.
Managing elastic properties of ABX type molecular perovskite ferroelectrics is critical to their future applications since these parameters determine their service durability and reliability in devices. The abundant structural and chemical viability of these compounds offer a convenient way to manipulate their elastic properties through a facile chemical approach. Here, the elastic properties and high-pressure behaviors of two isostructural perovskite ferroelectrics, MDABCO-NH I and MDABCO-KI (MDABCO = N-methyl-N'-diazabicyclo[2.2.2]octonium) is systematically investigated, via the first principles calculations and high-pressure synchrotron X-ray diffraction experiments. It is show that the simple replacement of NH by K on the B-site respectively results in up to 48.1%, 52.4%, and 56.3% higher Young's moduli, shear moduli and bulk moduli, which is attributed to the much stronger KI coordination bonding than NH …I hydrogen bonding. These findings demonstrate that it is possible to tune elastic properties of molecular perovskite ferroelectrics via simply varying the framework assembling interactions.
控制ABX型分子钙钛矿铁电体的弹性性质对其未来应用至关重要，因为这些参数决定了它们在器件中的服役耐久性和可靠性。这些化合物丰富的结构和化学活性提供了一种通过简便的化学方法来调控其弹性性质的便捷途径。在此，通过第一性原理计算和高压同步辐射X射线衍射实验，系统地研究了两种同结构钙钛矿铁电体MDABCO-NH I和MDABCO-KI（MDABCO = N-甲基-N'-二氮杂双环[2.2.2]辛鎓）的弹性性质和高压行为。结果表明，在B位上用K简单取代NH分别导致杨氏模量、剪切模量和体模量提高了48.1%、52.4%和56.3%，这归因于KI配位键比NH…I氢键强得多。这些发现表明，通过简单改变骨架组装相互作用来调节分子钙钛矿铁电体的弹性性质是可能的。
