Preparation of anatase nanocrystallines from low concentration precursor solution via a microwave assisted liquid phase deposition (MW-LPD) process

Nanocrystalline titanium dioxide in the anatase phase was successfully prepared via a facile microwave assisted liquid phase deposition (MW-LPD) process with hexafluorotitanate ammonium (NH4)2TiF6 as precursor. Compared with the conventional LPD processes, the MW-LPD technique could provide quickly high yield and crystallinity in a diluted precursor solution at low temperature because the high-frequency microwaves penetrated into the bulk of the material and the volumetric interaction of the electromagnetic fields with the material results in dielectric (volumetric) heating. This led to higher heating efficiency with faster processing. The X-ray diffraction (XRD) and selected-area electron diffraction (SAED) studies on these powders indicated that the powders obtained with MV irradiation have much higher crystallinity with a single phase anatase. Their photocatalytic activities were also investigated by the photodegradation of methylene blue (MB) as a model molecule.