Facile synthesis and enhanced photocatalytic properties of truncated bipyramid-shaped anatase TiO_2 nanocrystals

摘要

Truncated bipyramid-shaped anatase TiO_2 nanocrystals bound by eight {101} facets and two {001} facets have been synthesized by a facile solvothermal approach with the aid of HF and H_2O_2. The influences of synthetic parameters, such as the volume of HF and H_2O_2 aqueous solution, on the sizes and shapes of the resulting TiO_2 nanocrystals have been investigated. It is found that the shapes of TiO_2 nanocrystals can be evolved from nanosheets to truncated nanobipyramid with decreasing the volume of HF solution in the presence of H_2O_2 aqueous solution. Photocatalytic measurements show that truncated bipyramid-shaped TiO_2 nanocrystals exhibit improved photocatalytic activity of methyl orange in comparison with commercial-grade Degussa P25 TiO_2 nanoparticles due to the high exposure of {001} facets.