Large single-crystal anatase TiO2 Bipyramids

In this study, large single-crystal anatase TiO2 bipyramids were first successfully synthesized using a simple hydrothermal route. The synthesized bipyramids were characterized by XRD, SEM and TEM measurements, and found that these bipyramids are highly crystalline anatase TiO2 with a size up to 3.6 μm between the two ends. On the other hand, it was also found that the size and shape of bipyramids were significantly influenced by the pH value. Based on a series of experimental results, a possible model for the process of dissolving-coalescing-growing, has been proposed for the formation of large anatase TiO2 bipyramids.