Designing Functional Polyoxometalate-Based Ionic Liquid Crystals and Ionic Liquids

Polyoxometalate (POM) compounds constitute a wide family rich of more than several thousand inorganic compounds which can be finely tuned at the molecular level. Considering the high diversity in their structures and properties, the incorporation of such inorganic components into liquid crystalline phases or ionic liquid phases is particularly relevant for the elaboration of functional materials. By adjusting the molecular structures of the anions and the nature of the counter cations, many authors designed different types of mesophases sometimes with application in optoelectronics, or true POM-based ionic liquids (POM-ILs with melting temperatures below 100 degrees C). The latter turn out to be highly interesting for various applications in catalysis, depollution, or protection of the historical heritage. This review focuses on the recent developments in these organic/inorganic hybrid materials, POM-based ionic liquid crystals and POM-ILs, and their applications.