Preparation and Photocatalytic Performance of Anatase/Rutile Mixed-Phase TiO 2 Nanotubes

Anatase-dominated anatase/rutile mixed-phase TiO 2 nanotubes were prepared by decorating TiO 2 on the hydrothermally synthesized TiO 2 -derived nanotubes via liquid phase deposition and subsequent annealing. The morphology and structure of as-prepared TiO 2 nanotubes were characterized by transmission electron microscopy, X-ray diffraction, Raman spectra, and UV–Vis diffuse reflectance spectra. The separation efficiency of photogenerated carriers was investigated by photoluminescence spectra. The photocatalytic activity was evaluated by methyl orange decomposition under UV illumination. The results indicated that the mixed-phase TiO 2 nanotubes consisting of anatase and rutile (82/18 w/w) were successfully fabricated. Due to the synergistic effect of mixed anatase and rutile phases, the anatase-dominated anatase/rutile mixed-phase TiO 2 nanotubes exhibited superior photocatalytic activity. The apparent rate constant k of the photocatalytic reaction for the TiO 2 nanotubes with and without decoration was 0.0528 and 0.0126, respectively. Graphical Abstract Anatase/rutile mixed-phase TiO 2 nanotubes (MNTs) were prepared by hydrothermal synthesis and subsequent annealing. And anatase-dominated anatase/rutile mixed-phase TiO 2 nanotubes (ANTs) with superior photocatalytic performance were fabricated by decorating TiO 2 on hydrothermally synthesized TiO 2 -derived nanotubes via liquid phase deposition and subsequent annealing.