Preparation and Characterization of Anatase TiO2 Nanosheets-Based Microspheres for Dye-Sensitized Solar Cells

The one-pot synthesis of hierarchically structured anatase TiO 2 nanosheets-based microspheres with controlled sizes is successfully achieved through the hydrolysis of titanium tetrafluoride in polyol medium with heating at 170 °C. Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and X-ray photoelectron spectroscopy (XPS) are used to characterize the products. The effect of heat treatment on F – adsorbed on the surface of the nanosheets-based microspheres is investigated. In our work, fluorine ions from TiF 4, diethylene glycol (DEG) as a solvent as well as a protective capping agent, and excess acetic acid play important roles in the formation of the dominantly exposed {001} facets and hierarchical structure. Due to the dominant exposure of high surface energy {001} facets, enlarged surface area, and improved light-scattering effect of the anatase TiO 2 nanosheets-based microspheres, the dye-sensitized solar cell (DSSC) based on such materials exhibits cell performance superior to that of P25 TiO 2 .