Hydrothermal growth of rutile TiO2 nanorod films on titanium substrates

Rutile TiO2 nanorod films have been successfully prepared on titanium substrate via a hydrothermal method using Tetra-n-butyl titanate as Ti source in the presence of concentrated hydrochloric acid. The effect of Ti substrate annealing treatment and adding of additional alkali metal chlorides in hydrothermal solution on the growth of TiO2 nanorod films has been studied using scanning electron microscopy (SEM), Raman spectroscopy, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and water contact angle measurement. The growth mechanism of the TiO2 nanorods on Ti substrate has also been discussed. It has shown that the initial rutile film transformed from anatase promotes the nucleation and epitaxial growth of rutile TiO2 nanorods. The superior wettabilities of the TiO2 nanorods resulted from treatments of vacuum and ultraviolet show great potential for applications in orthopaedic, dental implants, and possible photocatalysis.