Synthesis, structural and optical properties of pure and rare-earth ion doped TiO2 nanowire arrays by a facile hydrothermal technique

•Rare-earth (RE) doped TiO2 nanowire arrays were prepared by hydrothermal method•RE doping enhanced the growth rate of TiO2 nanowire arrays•The catalysts used to check their photocatalytic activity by toludine blue-O dye•RE doped TiO2 act as unprecedented photocatalyst for organic dye decomposition

Single crystalline pure and rare-earth metal ions (Eu3 + and Ce3 +) doped TiO2 nanowire arrays were prepared on conductive fluorine doped indium tin oxide substrates by a facile hydrothermal method. Initially the conditions and parameters were optimized to prepare the high quality TiO2 nanowire arrays in the absence of organic additives. The average diameter and length of the TiO2 nanowire were found to be ~ 30–50 nm and ~ 0.5–1.5 μm, respectively. The formations of rutile phase structure in all the samples were confirmed by x-ray diffractometric analysis while the transmission electron microscopy confirms the single crystallinity and the maximum orientation of growth direction along [001] for the as-grown TiO2 nanowire. The optical properties of all the samples were analyzed using photoluminescence spectroscopy. The photocatalytic properties of the pure and doped TiO2 were investigated for the decomposition of organic toludine blue-O dye under ultraviolet irradiation. The result demonstrates that the Ce3 +: TiO2 decomposed almost 90% of the organic dye within 80 min.