Abstract: While preparing TiO₂ nano-powder, different additives and the ratio of mixed additives were
used as precipitants, different phases of crystalline and different ratios between rutile and anatase were gotten. The transitional
temperature from anatase to rutile is different with the same preparing approach and different processing manner of TiO₂ nano-powder. The
crystal phase of TiO₂ nano-powder is controlled by the type of precipitant, the ratio of different additives in the mixing solution
and preparing approach. It is also determined by the interaction between the powder’s face and the precipitants and the precipitant characteristics.
It depends on the stability of the interface phase during the growth of powder.

Key words: nano-powder, TiO₂, crystal phase, precipitant, transitional temperature, ratio