Microwave-Assisted Vacuum Synthesis of TiO₂ Nanocrystalline Powders in One-Pot, One-Step Procedure

A new method for fast and simple synthesis of crystalline TiO₂ nanoparticles with photocatalytic activity was developed by carrying out a classic sol-gel reaction directly under vacuum. The use of microwaves for fast heating of the reaction medium further reduces synthesis times. When the solvent is completely removed by vacuum, the product is obtained in the form of a powder that can be easily redispersed in water to yield a stable nanoparticle suspension, exhibiting a comparable photocatalytic activity with respect to a commercial product. The present methodology can, therefore, be considered a process intensification procedure for the production of nanotitania.