Fig. 2 shows the XRD patterns of the TiO2 nanoparticles,the TiO2s pheres prepared with using ammonia, and the TiO2 spheres prepared without using ammonia. It can be seen that main crystalline phase of our samples are anatase type, with the crystal facets being labeled directly on the figure. The TiO2 spheres prepared with using ammonia containing a little brookite phase.It can be seen that adding ammonia in hydrothermal reactions can induce better crystallization.