Sm2O3/ZnO nanoparticles were prepared via microwave-assisted hydrothermal and sol-gel combustion synthesis. Characteristics of obtained samples were compared in dependence of Sm2O3 content and calcination temperature. Prepared nanostructures were characterized with scanning electron microscopy and X-ray diffraction. Nanoparticles prepared via microwave-assisted hydrothermal and sol-gel method have flower-like and spherical shape respectively. The photocatalytic activity of samples under solar light simulated illumination was found to be affected by content of Sm2O3, calcination temperature and preparation method. The first-order rate constant of MB solution degradation of samples prepared via microwave-assisted hydrothermal method approximately three times exceeds that of sol-gel samples.

In this study Sm2O3/ZnO and Eu2O3/ZnO nanostructures were prepared using microwave-assisted hydrothermal method. Effect of Sm2O3 and Eu2O3 content and calcination temperature was investigated. The reusability of obtained photocatalysts was also studied. The prepared samples were investigated by using XRD, X-ray spectroscopy, scanning electron microscope. The photocatalytic activity was determined by degradation of methylene blue (MB) under Osram Vitalux illumination. Modified ZnO nanoparticles according to XRD analysis consists of ZnO with crystallite size in the range of 16-23 nm. Under solar light simulated radiation prepared ZnO nanostructures shown high photocatalytic activity. After 30 minute of irradiation more than 95 % of initial MB solution was degraded. The photocatalytic test revealed that ZnO containing Eu2O3 and Sm2O3 exhibits higher activity than pure unmodified ZnO.

In this study ZnO photocatalysts with different loading of Eu2O3 and Sm2O3 were prepared vie microwave-assisted hydrothermal method. The prepared samples were investigated by using XRD, SEM and BET analysis. The photocatalytic activity was determined by degradation of methylene blue (MB) under Osram Vitalux illumination. Prepared ZnO photocatalysts shown high photocatalytic activity under solar light simulated radiation. After 30 minute of irradiation more than 95 % of initial MB solution was degraded. The effect of pH and photocatalyst dosage was investigated. The reusability of photocatalysts was also studied.

In order to improve TiO2 photocatalytic activity ZnFe2O4/TiO2 nanocomposites with different ZnFe2O4 mass loading were produced. Obtained ZnFe2O4 nanoparticles were coupled with TiO2 via microwave-assisted hydrothermal method in order to improve photon absorption in a range of visible light. Prepared nanostructures were characterized with scanning electron microscopy and X-ray diffraction. Photocatalytic activity of prepared samples was investigated by degradation of methylene blue under different light sources – LED, Hg and Osram Vitalux lamps. ZnFe2O4 consists of spherical nanoparticles with average size of 15 nm. TiO2 spherical nanoparticles size is in a range of 30÷45 nm. The results show that doping TiO2 with ZnFe2O4 nanoparticles increases photocatalytic activity. Photocatalytic activity increases as mass loading of ZnFe2O4 decreases.