Sonochemical preparation of mesoporous titania submicrospheres for efficient dye-sensitized solar cells

Three-dimensional and thermally stable mesoporous TiO 2 submicrospheres are synthesized without the use of any surfactants via treatment with high intensity ultrasound irradiation for a short period of time. Techniques of X-ray diffraction, field emission scanning electron microscopy , nitrogen adsorption-desorption, and UV–vis spectrum are used to characterize the structure and morphology of the product. The specific surface area of the mesoporous TiO 2 submicrospheres is calculated to be 53   cm 2   g −1 . The UV–Vis spectrum shows that the mesoporous TiO 2 submicrospheres have high light-scattering ability and light absorption by dye. In addition, when applied as the light-scattering layer in dye-sensitized solar cell, an overall photovoltaic conversion efficiency of 7.92% has been achieved, significantly higher than that derived from P25 electrode (6.32%).