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In this study, un-doped ZnO and Zn1– xCexO (x = 0.01, 0.03, 0.05 and 0.10% wt) particles surface, structural, optical, morphological and photocatalytic activities were investigated. Un-doped ZnO and Ce-doped ZnO nanoparticles were synthesized via the sol-gel synthesis method. The crystal structure and possible impurities of the obtained nanoparticles were analyzed by X-Ray diffractometry (XRD). It has an X-ray diffraction pattern in which all dust particles match ZnO in the wurtzite structure, the range of average crystallite size 33 - 49 nm. Surface morphology and particle size were characterized by SEM analysis. Compared to undoped ZnO, the bandgap of Ce-doped ZnO is less and this depends on the proportion of doped. The forbidden bandgap energy (Eg) measurement result is between 3.07 eV and 2.94 eV with % Ce doped to ZnO. Rate constant value (k-1) was determined for Ce-doped ZnO at 0.01, 0.03, 0.05 and 0.10%, respectively. Results showed that the k-1 value at un-doped ZnO doped is 0.00801 ± 0.00243 min−1. In contrast, k significantly increased to 0.01719 ± 0.00286 by 1% Ce doped in the ZnO matrix. The effect of the synthesized nanoparticles on the dye under visible light was investigated using Rhodamine B (RhB) dye. All results showed that 1% Ce-doped ZnO has the highest photoactivity (96.67%) among all samples. [ABSTRACT FROM AUTHOR]

Photocatalysis under visible light is a promising method for the removal of environmental pollution by solar energy. Nowadays, interest in metal oxides as photocatalysis is increasing. In the study, Ag@ZnO/TiO2 nanocomposite particles were synthesized using the hydrothermal method. Nanocomposite particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The photocatalytic effects of the synthesized samples on methylene blue, rhodamine B, and malachite green aqueous solutions under Xenon light were investigated. Photocatalytic degradation properties of the samples were evaluated by calculating the absorbance decreases in the UV–Vis absorption spectra (methylene blue 664 nm, rhodamine B 554 nm, malachite green 617 nm). It was observed that the photocatalytic effect of the zinc doped TiO2 composite sample in all applied dyestuffs was higher than in other samples. Furthermore, it was reported that zinc doped TiO2 nanocomposites had 99.85% degradation on methylene blue, 98.41% on the malachite green after 120 min, and 99.29% for rhodamine B at the end of 60 min. [ABSTRACT FROM AUTHOR]

Purpose of this study is to investigate effect of gadolinium (Gd) content of GdxFe2O3(100-x), (x = 0, 5, 10, 20) composite system on structural, thermal, optical and radiation protection of poly (vinyl alchool) PVA based nanocomposite film. In this study, Gd doped Fe 2 O 3 nanopowders (with Gd = 0, 5, 10 and 20) were synthesized by spray pyrolysis method. The characterization of these powders have been obtained by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and Uv-vis spectrometer. After then, GdxFe 2 O 3 (100-x)/PVA (x = 0, 5, 10, 20) polymer composite systems were prepared by solution casting technique. The structural, thermal and optical properties of obtained polymer composites have been examined. The irradiation properties of 6 MeV energized X-ray via cLINAC to obtain radiation shielding performance of these different percentage (0, 5, 10, and 20%) Gd doped Fe 2 O 3 PVA thin films were also investigated. By using obtained results, the Linear Attenuation Coefficient (LAC), Half Value Layer (HVL), Tenth Value Layer (TVL), Mass Attenuation Coefficient (MAC). Also, theoretically Z eff value have been calculated. According to all obtained results, it has been seen that the different percentages (0, 5, 10, and 20%) Gd doped Fe 2 O 3 PVA thin films can be used as radiation shielding material., (Copyright © 2021 Elsevier Ltd. All rights reserved.)