Low temperature synthesis and photocatalytic activity of rutile TiO2 nanorod superstructures

Pure rutile nanorods were synthesized by hydrolysis of TiCl4 ethanolic solution in water at 50 degrees C. The assembly of rutile nanorods could be controlled through simply changing the molar ratios of TiCl4, ethanol, and water, resulting in different superstructures with flower- or urchinlike morphologies. The resulting samples were characterized with X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, nitrogen sorption, and UV-vis diffuse reflectance spectrum. A possible mechanism for the growth and assembly of rutile nanorod superstructures was proposed on the basis of characterization results. More importantly, we found that those low temperature synthesized superstructures showed significantly higher photocatalytic activities than commercial photocatalyst P25 on degradation of rhodamine B in water under artificial solar light. This study provides a simple and inexpensive way to prepare high active rutile nanorods superstructures photocatalysts on a large scale.