Cerium-doped mesoporous BaTiO3/TiO2 nanocomposites: structural, optical and photocatalytic properties

Nanoscale composite materials based on cerium, barium titanate and titanium dioxide were synthesized by thermal hydrolysis. The obtained individual TiO2, BaTiO3 and as-synthesized Ce/xBaTiO(3)/TiO2 semiconductive nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive spectrometry, transmission electron microscopy, nitrogen adsorption-desorption, UV-vis diffuse reflectance spectroscopy, and Fourier transform infrared spectroscopy. The structural investigations revealed that all prepared powders were nanocrystalline with an average crystallite size within the range of 5-17nm. Analysis of nitrogen adsorption-desorption isotherms for the synthesized nanocomposites showed the presence of a hysteresis loop, which is evidence for the mesoporous structure of the powders. The photocatalytic degradation of the model pollutants (SafranineT and Rhodamine B) was carried out under UV irradiation. Ce/xBaTiO(3)/TiO2 nanocomposites showed higher photocatalytic activity compared to pure TiO2 and BaTiO3 as well as BaTiO3/TiO2. An increase of the amount of BaTiO3 in Ce/xBaTiO(3)/TiO2 samples by more than 12% reduces the photocatalytic activity of nanocomposites while doping of BaTiO3/TiO2 samples with cerium increases their photoactivity.