Refluxing Synthesis of Anatase TiO₂ Nanoparticles Assembled Microprisms and Its Application for Dye-Sensitized Solar Cells

Anatase TiO₂ nanoparticles-assembled microprisms with high specific surface area (222.21 m²/g) were successfully fabricated via a simple refluxing method, based on hydrolysis of titanium glycolate precursor and water. The crystal phase, size, and properties of the TiO₂ microprisms were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), Raman, and Brunauer-Emmett-Teller (BET) methods. It was proposed that water can slowly permeate into the prism-like titanium glycolate microstructures during refluxing, resulting in the formation of prism-like TiO₂ microstructures by the assembling of nanoparticles. Dye-sensitized solar cells (DSSCs) fabricated with the prepared TiO₂ nanoparticle-assembled microprisms photoanode showed an overall light-toelectricity conversion efficiency of 2.4% with a short-circuit current density of 7.46 mA cm^-2, an open-circuit voltage of 0.686 V, and a fill factor of 46.1%.