Synthesis and physicochemical characterization of titanium oxide and sulfated titanium oxide obtained by thermal hydrolysis of titanium tetrachloride

Abstract

-This work reports the synthesis of titanium oxide (TiO 2 ) and sulfated titanium oxide (TiO 2 -SO 4 2-) obtained by thermal hydrolysis of titanium tetrachloride. Titanium hydroxide synthesized by this method was impregnated with a 1 N H 2 SO 4 solution, to give amounts of sulfate ions (SO 4 2-) of 3 and 7 wt%. The synthesized samples were dried at 120 °C during 24 h and then calcined for 3 h at 400 °C. Thermal analyses, X-ray diffraction, nitrogen physisorption, infrared spectroscopy, potentiometric titration with n-butylamine, U.V.-visible diffuse reflectance spectroscopy and scanning electron microscopy were used to characterize the materials. The results of physicochemical characterization revealed that a mixture of crystalline structures, anatase, brookite and rutile developed in the titanium oxide, stabilizing the anatase structure in the sulfated titanium oxides, and coexisting with a small amount of brookite structure. The synthesized mesoporous materials developed specific surface areas between 62 and 70 m 2 g -1, without detecting an important influence of sulfation on this parameter. The presence of sulfate ions improved the acidity of titanium oxide and modified the characteristics of light absorption in the 425-600 nm region, which suggests the possibility of using these materials in reactions assisted by visible light.

Conversion of Glucose into 5-Hydroxymethylfurfural and Levulinic Acid Catalyzed by SO42–/ZrO2 in a Biphasic Solvent System

“…Temvuttirojn et al used XRD to analyze the synthesized SO 4 2– /ZrO 2 and found that the peak intensity would decrease after impregnation with sulfuric acid because the surface of ZrO 2 was anchored by SO 4 2– . There are also other studies demonstrating that the sulfation treatment can inhibit the crystallization of metal oxides, thereby weakening the peak intensity of its XRD diffraction peaks …”

Synthesis and Characterization of Novel Green Hybrid Nanocomposites for Application as Proton Exchange Membranes in Direct Borohydride Fuel Cells

“…The FTIR spectra of TiO 2 -based doping agents and TiO 2 are compared in Figure 2. TiO 2 bands located at 715 and 1026 cm −1 are attributed to Ti-O bonds, and the bands at 3387, 1622 and 1396 cm −1 correspond to O-H bonds due to the moisture sorption on the powder surface [23]. In the case of SO 4 -TiO 2 , a strong band at 1153 cm −1 is attributed to sulfate ion coordinated to the Ti 4+ metal cation.…”

“…The functionalization of TiO 2 either with the PO 4 3− anion or SO 4 2− anion was done by an impregnation-calcination method according to the literature [22][23][24] and is explained briefly herein. The PO 4 -TiO 2 powder was obtained as follows: TiO 2 powder was mixed with 0.1 M H 3 PO 4 in a 1:1 molar ratio and the solution was shaken in a water bath (80 • C).…”

A Highly Selective Novel Green Cation Exchange Membrane Doped with Ceramic Nanotubes Material for Direct Methanol Fuel Cells

“…the bands at 1622 cm −1 refer to the bending vibration of the Ti-OH band. The band at 3387 cm −1 are assigned to O-H stretching vibration bonds due to moisture adsorption on the material's surface [20,33]. For the chart of PO 4 -TiO 2 particles, the band at 690 cm −1 corresponds to the stretching of the Ti-O bond.…”