The Study of Growth and Coagulation of Titania Nanoparticles by Chemical Vapor Synthesis

Chemical Vapor Synthesis (CVS) route was used for synthesis of titanium dioxide (TiO) nanoparticles in hot-walled reactor at 800°C using TiCl as precursor. The effect of processing parameters e.g., temperature and amount of precursor on phase structure, size, purity, coagulation and agglomeration of nanoparticles were investigated in this respect. Also, the HO effects on the size, crystallinity, phase transformation and purity of nanoparticles were studied. Comprehensive experimental observations were confirmed by transmission electron microscopy (TEM), X-ray diffraction analysis and TG-DTA results. The obtained results showed that by increasing the precursor amount and temperature, no phase transformation can be observed but the size, coagulation and agglomeration of titania nanoparticles increase. Also, the results showed that by introducing water vapor, the average particle sizes decrease saliently and no phase transformation and impurity were observed. Titanium dioxide nanoparticles can be used for synthesis of nanofluids. Nanofluids (nano-TiO¬¬water) as a cooling agent can be used for the enhanced economy and safety of the nuclear reactors.