Abstract

Sols prepared by chelation of titanium n-butoxide, Ti(OC4H9)4, with ethyl acetoacetate, C6H10O3, in various ratios were slowly hydrolyzed, and the obtained gels were investigated using Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis. The gels were thermally treated at 350 °C, and the products were investigated using X-ray diffraction, N2 gas adsorption–desorption isotherms and diffuse reflectance UV–Vis spectroscopy. Photocatalytic activity assessment was obtained through degradation process of methylene blue under UV light. From the results obtained, the relationships between gel structure and titania crystallite size, specific surface area, bandgap, and photocatalytic activity, as the most relevant parameters, were discussed. The alkoxide modification affected the gel structure, as well as the properties of the final material. However, the sample prepared from unmodified Ti-n-butoxide yielded the most favorable properties.

Key words: Nanocrystalline anatase; photocatalytic activity; bandgap; ethyl acetoacetate; chelating agent.