Organic Enantiomeric Ferroelectrics with High Piezoelectric Performance: Imidazolium <scp>l</scp>- and <scp>d</scp>-Camphorsulfonate
作者:Lei Xu、Xin Mu、Xiao-Gang Chen、Han-Yue Zhang、Ren-Gen Xiong
DOI:10.1021/acs.chemmater.1c01663
日期:2021.7.27
Ferroelectric materials have been widely used in daily life and industrial production, as memories, transducers, capacitors, sensors, and so forth. Recently, great interest in molecular ferroelectrics has emerged because of their structural flexibility, tunability, and homochirality. Chemical design has opened up a new era for molecular ferroelectrics, where we can realize the targeted design and performance optimization of molecular ferroelectrics upon several well-developed phenomenological theories. Herein, through the chemical design strategies of lowering the molecular symmetry and introducing homochirality upon the nonferroelectric imidazolium methanesulfonate (ImMS), we designed a pair of high-temperature organic enantiomeric ferroelectrics, imidazolium l-camphorsulfonate (l-ImCS) and imidazolium d-camphorsulfonate (d-ImCS). The enantiomers undergo a 222F2-type ferroelectric phase transition at 367 K (Tc(l)) and 370 K (Tc(d)), respectively. It should be highlighted that l- and d-ImCS show a relatively high piezoelectric response of 19 and 20 pC N–1, reaching the level of triglycine sulfate. To our knowledge, this is the first time that homochiral small-molecule ferroelectrics possess such a large piezoelectric response as well as good biocompatibility. This finding provides a new and feasible strategy for precisely designing high-performance homochiral molecular ferroelectrics.
铁电材料在日常生活和工业生产中被广泛应用,例如在存储器、传感器、电容器和传感器等方面。近期,分子铁电材料引起了广泛关注,因为它们具有结构灵活性、可调性和单一手性。化学设计为分子铁电材料开辟了一个新时代,使我们能够基于若干成熟的现象理论实现分子铁电材料的目标设计和性能优化。在本文中,通过降低分子对称性和在非铁电的咪唑铵甲磺酸盐(ImMS)中引入单一手性,我们设计了一对高温有机手性铁电材料,咪唑铵l-樟脑磺酸盐(l-ImCS)和咪唑铵d-樟脑磺酸盐(d-ImCS)。这对对映体分别在367 K (Tc(l)) 和 370 K (Tc(d)) 处经历222F2型铁电相变。需要强调的是,l-和d-ImCS的压电响应分别为19和20 pC N–1,达到了三甘氨酸硫酸盐的水平。据我们所知,这是首次单一手性的微小分子铁电材料展现出如此大的压电响应以及良好的生物相容性。此发现为精确设计高性能单一手性分子铁电材料提供了一种新的可行策略。