Heterogeneous solvothermal synthesis of one-dimensional titania nanostructures on transparent conductive glasses

The present study reports a novel method for a direct growth of one-dimensional (1D) TiO ₂ nanoarchitectures on fluorine-doped tin oxide (FTO) conductive glass by a heterogeneous solvothermal route. Results indicate that the morphologies of the obtained samples can be controlled and changed from vertically oriented single-crystalline rutile nanowire arrays to randomly disoriented nanotubular architectures by controlling the position of the substrate and the amount of the initial precursor. At a low concentration of the precursor, dandelion-like TiO ₂ comprised of large amounts of the crystalline nanorods are found on the nonconductive surface of the horizontally oriented FTO glass, which are suitable for photocatalysis, while TiO ₂ nanowire arrays are grown on the conductive surface of the FTO glass, which can be used as photoanodes for sensitized solar cells to enhance the electron-transport rate. The difference in morphology is probably related to the selective adsorption of the Cl ions, the texture of the substrate, and the immiscibility between the nonpolar solvent and the aqueous solution.