(70an) Preparation of Titania Nanoparticles and Its Photocatalytic Properties

Spherical TiO₂ nanoparticles were synthesized from titanium tetraisopropoxide (TTIP) precursor by flame spray pyrolysis. The effects of key experimental variables such as the molar concentration of the precursors and the flow rates of combustion gages on the properties of as-prepared particles were investigated systematically. Regardless of the precursor concentration, the as-prepared TiO₂ nanoparticles were spherical, non-aggregated, and non-hollow, and also showed high crystallinity. As the precursor concentration increased, the average primary particle diameter increased. Contrary, raising the flame temperature by controlling the gas flow rates led to a decrease in the average diameter of the particles. Color-removal by the degradation of methylene blue ranged from 99 to 92% in 1 hr using the TiO₂ nanoparticles of the different average particle diameters.