Arrays of templated TiO2 nanofibres as improved photoanodes for water splitting under visible light

Arrays of TiO2 nanofibres (NFs) were successfully prepared by template sol-gel synthesis, using track-etched polycarbonate membranes as structure directing agent. The control of the sol-gel kinetic was crucial in order to homogeneously fill the pores with a continuous framework. For this reason acetylacetone was added to the sol-gel mixture as chelating agent. The band edge positions of TiO2 NFs were determined by a Mott-Schottky plot and diffuse reflectance analysis. The results support the presence of trace dopants which can act favorably with respect to the photoelectrochemical properties. The TiO2 NFs array showed enhanced photoelectrochemical activity both under UV light and visible light when used as photoanodes for the water splitting reaction.