Inorganic-Organic Hybrid Materials Based on Nanopolyoxometalates

Abstract

Various types of nano-scale polyoxometalates (POMs) with beautiful topologies has been synthesized successfully by destroying the hydration shell of the anions caused by the extremely hydrophilic surface. Their magnetic, electronic, and photoluminescent properties and valuable applications in catalysis, medicine, and material science are discussed. Meanwhile, the last ten years have witnessed a remarkable development in terms of preformed organic-inorganic POM-based hybrid systems for the rational design of functional architectures, assemblies and materials. Hydrophilic POMs of different sizes and shapes can interact with hydrophobic cationic surfactants, the resulting materials show amphiphilic properties with electrostatic interactions between the hydrophilic and hydrophobic components, called Surfactant-Encapsulated Clusters (SECs) or Surfactant-Encapsulated-POMs (SEPs). This hydrophobic surfactant-encapsulated clusters (HSECs) can fabricated through covalent or non-covalent interaction, which can construct ordered self-assembly, e.g. robust onionlike structures, honeycomb films or giant vesicle. Moreover, This ordered giant vesicle acts as building block to fabricate three dimensional structures. In addition, SECs can further self-assemble to give a variety of nanostructures on various surfaces/interfaces, among them, the most representative nanostructures discussed below is ordered honeycomb films, which is carried out by a simple solvent-evaporation method. It is reasonable to assume that the condensed water microdroplets induced by the quick evaporation of solvents play an important role as template for the formation of pores. Various factors are being investigated to construct thin films with different morphologies. We hope the inorganic-organic hybrid functional materials based on POMs will bridge polyoxometalate chemistry and material chemistry, which can be further explored application in many fields.