Hybrid/porous materials obtained from nano-emulsions

Nano-emulsions known also as mini-emulsions, ultrafine emulsions or submicron emulsions are a specific kind of emulsions that have a sub-micrometer droplet size and a low polydispersity. Nano-emulsions, being kinetically stable systems, require energy input in order to be formed, either from mechanical devices or from the intrinsic physicochemical potential of the components. The properties of the nano-emulsions make them suitable for applications in various domains such as drug delivery, cosmetics, pesticides and in particular for the preparation of inorganic or hybrid nanostructured materials. This review discusses the recent progresses made in this latest field. We focus on inorganic or hybrid nanoparticles, nanocapsules, hollow spheres or composites prepared by combining the nano-emulsion technique and the sol–gel process. In that case nano-emulsions act as template. We also outline the most recent development, which consists in using the nano-emulsions as imprints to get hierarchical porous silica materials.