Influence Factors on Preparing Process of TiO_2 Nanoscale Particles

The preparing process of TiO2 superfine perticles from homegeneous solutions was investigated by a new instrument designed (China patent). The effect of pH, concenteration of reactal, anions present on the characteristics of final products was discussed,and rutile TiO2 particles about 100nm were obtained. With this instrument,the hydrolysis process can directly be recorded. The beginning time (t1) and temperature (T1) of hydrolysis,the parameters of I/I0 (generated nucleus concentration),△T(nucleus-forming temperature range), △t(nucleus-forming time range)can also be recorded.The relationship between generated nucleus concentration and temperature, time in different conditions was obtained.It is shown that the changes of reactant concentration and pH values,anion cause the variety of t1, T1, △t, △T. The characteristics(size,crystalline)of the product depend on these paramaters.The higher the beginning temperature of the hydrolysis,and the narrower the temperature range,the faster the hydrolysis reaction, the smaller the particles size and the more difficult the crystalline transforming.