具有钙钛矿结构的多轴分子铁电体

Molecular ferroelectrics have the advantages of easy processing, less pollution, energy saving, variety, easy regulation and easy film formation. It can replace inorganic oxide ferroelectrics in some applications and will become the bridge to connect oxide and composite soft material. However, molecular ferroelectrics are limited by the structure, most of which have relatively low symmetry and are uniaxial, greatly hindering their practical application. The project aims to carry out the search and research work of the perovskite-structure multiaxial molecular ferroelectrics. Through the structural and symmetrical regulation, we would search and design the novel perovskite multiaxial molecular ferroelectric materials, and fabricate the corresponding ferroelectric thin films. Meanwhile, we would also carry up a systemic in-depth study about their structures, ferroelectricity, dielectric and multifunction, and sum up the relationship between structure and property. Moreover, the mechanism of these ferroelectrics would be deeply studied to lay the foundation for the future design and application of molecular ferroelectric materials.

分子基铁电体具有易加工、污染少、节能、种类多、易调控和易成膜等优点，在某些应用方面能够替代无机氧化物铁电体，并将成为沟通氧化物和复合软材料的桥梁。但分子铁电体受结构所限，大多结晶于对称性相对较低的空间群之中，为单一铁电极轴，大大限制了分子铁电体的应用。项目拟开展钙钛矿结构多极轴分子铁电体的寻找和研究工作，通过结构和对称性调控，寻找与设计新颖的钙钛矿结构多极轴分子铁电材料并制备其分子铁电薄膜，对其结构、铁电、介电与多功能性进行系统深入的研究，总结结构与性质之间的联系，深入探讨该类铁电体的铁电机理，为今后分子铁电材料的设计和应用打下基础。

项目围绕具有钙钛矿结构的有机-无机杂化分子材料的设计，利用准球型有机分子策略、卤代策略、氟代策略和手性策略，成功获得了一些多极轴分子铁电体，也获得了不少铁弹体和可作为光电开关的一般相变材料。对获得的相关相变材料都系统深入地进行了结构、介电、铁电、铁弹、半导体和光学性质等物理性质研究，探明了材料结构和性质之间的关系。在寻找多轴铁电体的研究探索中，总结了一些半经验的方法。相关研究发表了研究论文31 篇，在该基金的支持下，1名博士生取得博士学位，7名硕士生取得硕士学位。