基于柔性链状烷基胺构筑的有机-无机杂化型分子铁电晶体的设计合成、结构和性质研究

Ferroelectric materials have drawn great interest due to the various important application for date storage, infrared detection, electro-mechanical transformation and optoelectronic devices. Compared with traditional ferroelectric materials, further exploration of new organic-inorganic hybrid molecular ferroelectric, which would be a critical role in photovoltaic application, is strongly imperative. In this project, we plane to design a series of new organic-inorganic hybrid molecular ferroelectric constructed with flexible chain alkylamine and metal halide, where the molecule ferroelectric polarization could be controlled by changing molecular structure of the organic-inorganic hybrid compounds. On this basis, we will investigate the relationship between physical properties and structural mechanism to summarize the ferroelectric phase transition rule, which is in favour of exploration of ferroelectric materials with high phase transition temperatures and large saturated polarization. In summary, this project will supports and scientific basis for the preparation of novel organic-inorganic hybrid molecular ferroelectric.

铁电材料在光电技术领域中发挥着重要作用，特别是有机-无机杂化型的分子铁电晶体材料，由于其高的载流子迁移率以及快速的极化翻转时间，在光伏技术中具有广阔的应用前景。如何在有机金属框架中引入构型易变的结构基元，来构筑性能优异的有机-无机杂化型分子铁电材料是现在面临的一个关键科学问题。本项目拟采用柔性的链状烷基胺为结构基元，与金属卤化物进行有效组装，构筑新颖的有机-无机杂化型分子铁电晶体材料；进一步通过分子设计和修饰调整链状胺基元的分子构型与结构柔性，不断优化其与金属卤化物之间的组装方式，开发高相变温度、大饱和极化强度等性能优异的有机-无机杂化型分子铁电材料；在此基础上，生长大尺寸高质量的铁电单晶，并对其铁电性能和结构变化机制进行深入分析，总结铁电相变规律，为新颖的有机-无机杂化型分子铁电晶体的设计合成提供科学依据。

有机-无机杂化分子铁电体不仅具有自发极化特性，还表现出高的载流子迁移率、长的载流子寿命以及高的吸光系数，在光电技术中具有广阔的应用前景。本项目以金属卤化物为主体，通过引入柔性的链状烷基胺，构筑了一系列具有高居里温度、大饱和极化强度的有机-无机杂化分子铁电晶体材料，并对其结构、热学、电学、光学及铁电性能进行了深入的研究。此外，基于有机-无机杂化铁电晶体构筑了新颖的光电探测器件，分别实现了快速光电探测及光谱选择性响应。此外，我们对有机-无机杂化型铁电晶体的铁电性能和结构变化机制进行深入分析，揭示了功能结构基元之间的相互关联，阐明了材料结构-铁电性能之间的内在关系，为新颖的有机-无机杂化分子铁电体的设计合成提供了一定的科学依据。