Room temperature synthesis of rutile TiO2 and its application in dye-sensitized solar cells

Abstract

We prepared rutile TiO2 powders of good crystallinity by hydrolyzing a Ti(OC4H9)4 precursor at room temperature and by reprecipitation. X-ray diffraction (XRD) revealed that higher acidity, lower temperature, and specific amounts of Cl- as a medium result in rutile TiO2. This rutile TiO2 has an irregular rice-like structure. After adding the P105 (EO37PO56EO37) tri-block copolymer as a structural agent, the rutile TiO2 aggregated to form rough 350 nm spheres. These rough spheres have a greatly enhanced light harvesting efficiency and improved energy conversion efficiency in dye-sensitized solar cells. This is due to their high light scattering effect and larger surface area (109.5 m2 · g-1). By adding these large rutile spheres at a mass fraction of 25% to the over-layer of a TiO2 film composed of ~20 nm TiO2 particles as light scattering centers, the energy conversion efficiency of the dye-sensitized solar cells (DSSC) was 7.27%. This is a 17% increase in conversation efficiency compared with the DSSC based on a TiO2 photoanode without these rough rutile spheres. © Editorial office of Acta Physico-Chimica Sinica.