Synthesis of {100} facet dominant anatase TiO2 nanobelts and the origin of facet-dependent photoreactivity.

Sword-like anatase TiO2 nanobelts exposed with 78% clean {100} facets were synthesized and the facet-dependent photoreactivity of anatase TiO2 was investigated. By quantitative comparison with the reference {001} facets, the {100} facets possessed about ten-times higher active sites density than that on {001} facets, resulting in higher photoreaction efficiency. After the active sites density normalization, the {100} and {001} facets exhibited distinct wavelength-dependent photocatalytic performance, attributed to the anisotropic electronic structures in TiO2 crystals.