Catalyst-free low temperature synthesis of discrete anatase titanium dioxide nanocrystals with highly thermal stability and UVC-cut capability

A novel, facile, catalyst-free, and low temperature process for the synthesis of discrete anatase TiO₂ nanocrystals has been developed in the absence of stabilizing agent. The product was shown to be discrete anatase TiO₂ nanocrystals with a mean diameter of 4.97 ± 0.9 nm and a specific surface area of 393 m²/g. By varying the water content and precursor concentration, the particle size could be tuned. Also, the resultant colloid solution was quite stable even in the absence of stabilizing agent because of the coverage of EG molecules on the particle surface. In addition, the anatase TiO₂ nanocrystals obtained in this work had highly thermal stability even at temperatures up to 800 °C. Also, as compared to Degussa P25 TiO₂ powders, they exhibited stronger absorption at 200–350 nm and higher transmittance in the visible light region. Thus, the new approach proposed in this work was practicable for the synthesis of anatase TiO₂ nanocrystals, particularly for those requested to have highly thermal stability and UVC-cut capability.