Ferroelectric Metal-Organic Frameworks

Practical synthetic strategies for construction of ferroelectric Metal-Organic Frameworks (MOF) are underway though the search for new ferroelectrics is now still an empirics-driven activity. Hydrogen bonds are widespread in MOFs, while aggregates linked by hydrogen bonds may undergo phase transitions due to proton transfers, which lead to structural polarizations. Dynamics of the guest molecules or ions may arouse complex structural phase transitions that reflect details of interactions between the host and the guest. In spite of great progress being made, research and applications of ferroelectric MOFs are still restricted by lack of basic understanding of ferroelectricity that needs extensive exploration. Coexistence or coupling between ferroelectricity and other physical properties such as magnetism, porosity, chirality, photoresponse, and optical properties may afford new types of materials and physical phenomena.