Nanocrystalline TiO2 micropillar arrays grafted on conductive glass supports: microscopic and spectroscopic studies

Vertically oriented TiO2 micropillar arrays were obtained on Fluorine-doped Tin Oxide (FTO) conductive glasses by adopting a facile and cost-effective method. The process consists in the spray-coating with a polymer film containing an organo-metallic precursor (Ti isopropoxyde), followed by scratching the film surface by means of a sandpaper and an oxidative treatment. The role played by the scratching step in the formation of vertically oriented TiO2 micropillars, as well as the nanostructured scaffold nature consequent upon the oxidation, will be highlighted. The morphology, structure and optical properties of samples, were investigated by combining electron and atomic force microscopies with X-ray diffraction and UV-vis spectroscopy. Due to the robust texture of highly crystalline and cemented anatase and rutile nanoparticles and to the porous nature of TiO2 pillars covering FTO glasses, this system may find application in energy, photochemistry and photodegradation fields.