Fabrication of phase-pure rutile nanocrystal by sol-hydrolysis of TiCl4 in aqueous solution at 95 °C only

Titanium dioxide (TiO2) nanoparticles of rutile phase were synthesized by hydrolysis of TiCl4 at 95 degrees C in aqueous solution. The samples as prepared and calcined at 500 T were characterized by XRD, TG-DTA and TEM. The sample as prepared was of imperfect rutile structure, and its morphology was rod-like with a diameter of 10 similar to 20 nm, a length of 20 similar to 80 nm and an aspect ratio of 2 similar to 4. The structure of the sample calcined at 500 degrees C was a perfect rutile one, and its morphology was rod-like with a diameter of 15 similar to 25 nm, a length of 25 similar to 105 nm and an aspect ratio of 2 similar to 4. These results indicate that calcination temperature has a positive effect on the structure and the size of rutile nanocrystals, and has no effect on the aspect ratio of rutile nanocrystal. A model for the formation mechnism of rutile nanocrystal in aqueous solution under hydrolysis conditions has been proposed.