Sol-Gel Obtaining of TiO2/TeO2 Nanopowders with Biocidal and Environmental Applications

TiO2/TeO2 powders were obtained by an aqueous sol-gel method. Telluric acid (H6TeO6) and titanium butoxide were used as precursors. The as-prepared gel was step-wisely heated in the temperature range 200-700 degrees C and subsequently characterized by XRD, IR, and UV-Vis analysis and SEM. Mixtures containing TiO2 (anatase), alpha-TeO2 (paratellurite), and TiTe3O8 were established by XRD as final products, depending on heating temperature. The thermal stability of the obtained gels in the temperature range 100-400 degrees C was investigated. It was found by IR spectroscopy that the samples heated up to 300-400 degrees C consist mainly of an organic-inorganic amorphous phase which is transformed into an inorganic one above these temperatures. The microstructure of the gels was verified by scanning electron microscopy (SEM). The photocatalytic degradation of the synthesized nanopowders toward Malachite green organic dye (MG) was examined in order to evaluate the potential applications for environmental remediation. The prepared TiO2/TeO2 samples showed up to 60% decoloration efficiency after 120 min exposure to UV-light. The composition exhibited good antimicrobial activity against E. coli K12. The properties of the obtained material were investigated by the reactions of complete catalytic oxidation of different alkanes and toluene, and it could be suggested that TiO2/TeO2 powders are promising material for use as an active phase in environmental catalysts.

Automated summary

TiO2/TeO2 powders were synthesized via sol-gel method using telluric acid (H6TeO6) and titanium butoxide as precursors. The as-prepared gel was heated in the temperature range of 200-700 degrees C and characterized by XRD, IR, UV-Vis analysis, and SEM. Depending on the heating temperature, the final products were identified as mixtures containing TiO2 (anatase), alpha-TeO2 (paratellurite), and TiTe3O8. The gels exhibited thermal stability and transformation from organic-inorganic amorphous phase to inorganic phase at higher temperatures. The photodegradation efficiency of the TiO2/TeO2 samples towards Malachite green dye and its antimicrobial activity against E. coli K12 were evaluated. Furthermore, the material showed promising potential as an active phase in environmental catalysts through catalytic oxidation reactions.