Controlling the synthetic pathways of TiO2-derived nanostructured materials

A comprehensive study of the hydrothermal synthesis of TiO2-derived nanostructured materials, including layered protonic trititanate (H2Ti3O7), metal-ion exchangeable titanate (Na(x)H(2-x)Ti3O7), TiO2(B) and anatase nanotubes and TiO2-anatase nanowires, was conducted. Nanoscaled tubular structures were found to be already present in the samples derived from prolonged hydrothermal process of bulk anatase TiO2 and could be converted to various types of nanotubes, nanowires or nanorodes by post-synthesis treatments. 0.1 M HCI acid wash and air annealing were the two key parameters to select the types of nanotubes/nanowires as the final products. XRD, Raman, TG, and XPS core level and valence band studies were carried out to elucidate our proposed synthetic pathways.