Electric Field-Responsive Framework Materials from Aromatic Building Blocks

目的：开发和测试电场响应晶体分子材料在技术应用中的可用性，如气体分离、机械驱动和信息存储技术。通过将电场相关响应集成到新的框架设计中，我们提出开发铁电晶体微孔聚合物（F-CMPs）来展示以下极具挑战性的技术应用：(a)晶体纳米电机，(b)用于2D/3D超高密度信息存储材料的可切换铁电体，以及(c)包含巨大和超快速开关响应的纳米致动器（人造肌肉）。方法：材料设计基于多孔共价有机框架（COFs）或含有偶极连接单元的金属有机框架（MOFs）。连接器将通过外部电场切换，以提供对这些框架晶格的结构和动力学的控制。将探索几种化学上不同的材料类别，包括kuratowski型亚基，以及鞍形和铰链状芳烃。所有框架化合物将通过热分析（TGA， DSC, VT-XRPD），孔隙度分析（BET表面积）以及各种光谱技术（UV-vis/NIR， FT-IR和拉曼光谱）的标准方法进行研究。特别是，这些框架的电场响应特性将使用拉曼光谱、双折射光谱和介电光谱进行研究。影响：该项目旨在开发铁电刺激响应材料，以应用于不同的（纳米）技术领域，包括技术上极具挑战性的工艺，如机械纳米致动器，包括巨大和超快的开关响应，以及2D/3D超高密度信息存储材料。国际合作的附加值：一个由两个研究团队组成的联盟，他们在有机合成和芳香材料（Stepien教授）和固态化学（Volkmer教授）领域的互补专业知识将涵盖铁电框架化合物的适当设计和工程的所有方面，包括其设想功能的原理验证研究。鉴于两家集团以前没有合作过，此次合作的附加值应该是非常大的。

Objectives: Electric-field responsive crystalline molecular materials will be developed and tested for their usability in technical applications, such as gas separation, mechanical actuation and information storage technologies. By integrating electric field-dependent responses into novel framework designs, we herein propose to develop ferroelectric crystalline microporous polymers (F-CMPs) to demonstrate the following, highly challenging, technical applications: (a) crystalline nanorotors, (b) switchable ferroelectrics for 2D/3D ultra-high density information storage materials, and (c) nanoactuators comprising giant and ultrafast switching responses (artificial muscles).Methodology: The material design is based on porous covalent organic frameworks (COFs) or metal-organic frameworks (MOFs) containing dipolar linker units. The linkers will be switchable by external electric fields, to provide control over the structure and dynamics of these framework lattices. Several chemically distinct classes of materials will be explored, containing Kuratowski-type subunits, as well saddle-shaped and hinge-like aromatics. All framework compounds will be investigated by standard methods of thermal analysis (TGA, DSC, VT-XRPD), porosity analysis (BET surface area) as well as by various spectroscopic techniques (UV-vis/NIR, FT-IR and Raman spectroscopy). In particular, the electric field-responsive properties of these frameworks will be investigated using Raman, birefringence, and dielectric spectroscopies.Impact: The project aims at developing ferroelectric stimulus-responsive materials toward applications in different fields of (nano-) technology, including technically extremely challenging processes, such as mechanical nanoactuators comprising giant and ultrafast switching responses, as well as 2D/3D ultra-high density information storage materials. Added value of international cooperation: A consortium of two research teams, recognized for their complementary expertise in the fields of organic synthesis and aromatic materials (Prof. Stepien) and solid-state chemistry (Prof. Volkmer) are going to cover all aspects of the appropriate design and engineering of ferroelectric framework compounds, including proof-of-principle studies of their envisioned functions. Given that the two groups have not collaborated before, the added value of the present cooperation should be very significant.