Electric Field-Responsive Framework Materials from Aromatic Building Blocks

• Applicant: Professor Dr. Dirk Volkmer
• Subject Area: Solid State and Surface Chemistry, Material Synthesis
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426506525

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.

• DFG Programme: Research Grants
• International Connection: Poland
• Partner Organisation: Narodowe Centrum Nauki (NCN)
• Cooperation Partner: Privatdozent Dr. Marcin Stepien