New route to prepare nanocrystalline TiO2 and its reaction mechanism

Titanium oxide nanoparticles are prepared by electrochemical dissolution of pure titanium in a mixed acetylacetone and ethanol solution followed by direct sol–gel process of the electrolyte. Infrared spectroscopy, Raman spectroscopy, X-ray diffraction, and TEM have been used to investigate the structure of precursor and nanocrystalline TiO2. Characterization of the electrochemical product reveals that Ti(OEt)m(acac)n was formed by anodic dissolution of titanium in a mixed acetylacetone and ethanol solution. Infrared experiments show that hydrolysis of Ti(OEt)m(acac)n precursor removes first OEt groups, the chelating acac groups are still observed in the gel and can only be removed upon heating to 473 K. This study also shows that nanocrystalline TiO2 prepared by this route has a textural and thermal stability with size distribution of 5–20 nm.