Hydrothermal Synthesis and Characterization of Nanorods of Various Titanates and Titanium Dioxide

Abstract

The formation process of titania based nanorods during hydrothermal synthesis starting from an amorphous TiO2.nH2O gel has been investigated. Sodium tri-titanate (Na2Ti3O7) particles with a rodlike morphology were prepared by a simple hydrothermal process in the presence of a concentrated NaOH aqueous solution. The ion exchange reaction of the synthesized Na2Ti3O7 nanorods with HCl under ultrasonic treatment promotes a complete sodium substitution and the formation of H2Ti3O7 nanorods. Low-temperature annealing of the as-produced nanorods of Na2Ti3O7 and H2Ti3O7 leads to a loss of the layered crystal structure and the formation of nanorods of condensed framework phases-sodium hexa-titanate (Na2Ti6O13) and metastable TiO2-B phases, respectively. These transformations proceed without a significant change in particle morphology. The nanostructures were investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), the Brunauer-Emmett-Teller (BET) method, thermogravimetric analysis (TGA), and Raman spectroscopy. The structural defects of the synthesized nanorods were investigated by high-resolution electron microscopy. The presence of planar defects can be attributed to the exfoliation of the zigzag ribbon layers into two-dimensional titanates as well as to the condensation of the layers of TiO6 octahedra into three-dimensional frameworks.

Insights into the multistep transformation of titanate nanotubes into nanowires and nanoribbons

“…The spectrum for sample hydrothermally treated at 150°C for 48 h is basically similar to that obtained by Kolen'ko et al [30] and Papp and co-workers [31] for H 2 Ti 3 O 7 . It also corresponds to the Raman spectrum presented for Na 2 − x H x Ti 3 O 7 ·nH 2 O titanates [20,21].…”

Synthesis and Characterization of TNTs/Polyaniline Composite as Photocatalyst Degradation of Rhodamin B by Visible Light

“…According to of TNTs has not been perfect. It can be seen from the TNTs structure which tend to be short and yet so irregular [7]. The results obtained were quite different to those that had been done by Ashraf et al [8].…”

An Overview Of Nanonet Based Dye-Sensitized Solar Cell (DSSC) In Solar Cloth

“…methods to synthesize nanowires such combining sol-gel processing with electrophoretic deposition, the spin-on process, anodic oxidative hydrolysis, sonochemical synthesis and more [40]. Hydrothermal method is a simple method which is where reaction among TiO 2 powders with alkaline solution [41] and the best method to synthesize nanowire recently.…”

“…Hydrothermal method is a simple method which is where reaction among TiO 2 powders with alkaline solution [41] and the best method to synthesize nanowire recently. The advantage of this technique is that nanorods can be obtained in relatively large amounts [40].…”