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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]

Blue fluorescent carbon dots are synthesized via a one-step hydrothermal method using rosemary leaves as a carbon source. The obtained carbon dots are characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis, FTIR, and fluorescence spectrometry. The results show that carbon dots gave a maximum emission peak at 422 nm when excited at 332 nm. The average particle diameter of the synthesized spherical carbon dots is found to be 16.13 nm with a 4.6-nm standard deviation. The diameters of the produced carbon dots vary, as is evident from standard deviation heights, resulting in multicolor emission spectra. The fruit storage experiment is carried out by investigating the qualitative antioxidant ability of the produced carbon dots. The results obtained for polyvinyl alcohol–carbon dot–coated samples differ remarkably compared to polyvinyl alcohol–coated samples only. The polyvinyl alcohol–carbon dot composition is used in latent fingerprint detection applications. In analyses made on a glass surface, fingerprints cannot be monitored on the glass surface with the polyvinyl alcohol layer under ultraviolet light, while they are observed on the surface covered with the polyvinyl alcohol–carbon dot composition. Moreover, biological activity against Gram-positive, Gram-negative, and yeast strains are investigated. [ABSTRACT FROM AUTHOR]

In this research work, a simple spray pyrolysis method was employed to synthesized gadolinium (Gd) doped titanium oxide (TiO2) thin film. The crystal structure and morphology of the sample was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). According to XRD measurements, no apparent crystal peak was observed. The thickness of the prepared film was found to be 228 nm from SEM observation. The optical transmittance and bandgap energy of the synthesized thin film was investigated by using UV-Vis spectroscopy. The high transmission of the thin film was found in the visible region. The optical bandgap energy of the prepared film was found to be 2.85 eV. The photocatalytic degradation of malachite green solution was studied. As a result of the photocatalytic experiment, the thin film could be used as an effective photocatalyst for malachite green dye. [ABSTRACT FROM AUTHOR]

In this study, iron oxide, nickel oxide, and nickel-iron oxide nanostructured particles were produced by the hydrothermal method. X-ray diffraction (XRD) and SEM measurements were performed to investigate the physical properties of these nanostructured particles. According to the XRD results, the crystal properties of these particles were determined. From the SEM images, these particles understood to be nano-structured. The electrodes were examined for electrochemical properties by using these nanostructured particles. Electrochemical measurements of the produced electrodes were performed, and capacitance values and impedance spectra of the electrodes were determined. The specific capacitance values of the iron oxide, nickel-iron oxide, and nickel oxide nanostructured particles, respectively are 30 F/g, 55 F/g, and 67 F/g. Also, the photocatalytic activities of nanostructured particles were investigated. This examination methylene blue (MB) was used and made under a xenon lamp. In light of our findings, it was observed that high photocatalytic degradation rate. Nickel-iron oxide nanostructured particles, the degradation of MB were found to be about 87%. [ABSTRACT FROM AUTHOR]

Boron doped vanadium thin films were fabricated on the micro-slide glass substrates by spray pyrolysis technique at substrate temperature of 400°C. Initially, 0.1 M vanadium(III) chloride (VCl3) solution was prepared in ethanol: water mixture (1: 4) solvent. To prepare the boron doped vanadium oxide films as the concentrations of 2, 5, 7, 10, 20%, the suitable amount of H3BO3 was added in 0.1 M VCl3 solution for each of the samples. X-Ray diffraction experiment with the produced films showed that tetragonal β-V2O5 phases formed. The synthesized boron-doped V2O5 thin films having the large surface area demonstrated the efficient catalytic properties in the photocatalytic degradation of methyl blue in water samples under Xenon light. The photocatalytic reaction efficiency was measured by recording the decrease of absorbance at 590 nm in UV-Vis absorption spectra. The methyl blue dye was degradated in approximately 30 min. The photocatalytic experiment results of the produced thin films showed that boron doping amount positively effects the degradation efficiency and reaction time. [ABSTRACT FROM AUTHOR]

Fluorine-doped ZnO (FZO) thin films were fabricated on glass substrates using a chemical spray pyrolysis method for NO 2 gas detection. The physical properties of the films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet–visible (UV–Vis) spectrometry as a function of fluorine concentration (2 and 5 at%). The films exhibited a hexagonal wurtzite structure, and the inclusion of fluorine did not significantly influence the morphology of the films. Optical measurements showed that the band gap energies of the films were affected by the fluorine concentration. Furthermore, the NO 2 gas-sensing properties of pristine and FZO thin films were investigated in the concentration range of 100–1000 ppb. Fluorine doping in ZnO was found to improve the NO 2 -sensing capability at the least. All gas sensor measurements showed an optimal sensor response at a temperature of 200 °C. In addition, the 2% FZO was found to be more suitable candidate for detecting NO 2 gas. [ABSTRACT FROM AUTHOR]

Yttrium oxide nanoflowers were prepared by a hydrothermal technique, and X-ray diffraction and scanning electron microscopy were used to determine their structures. The cytotoxic and genotoxic potentials of aqueous dispersions of the nanoflowers to cultured primary rat hepatocytes were examined at concentrations up to 500 mg L−1for 72 h. Cell viability was determined by monitoring the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, release of lactate dehydrogenase, and uptake of neutral red. Genotoxicity was assessed by the liver micronucleus assay. Exposure to Y2O3nanoflowers at concentrations lower than 100 mg L−1did not lead to any cytotoxicity or genotoxicity. At higher concentrations (200, 400, and 500 mg L−1), cell viability decreased and induction of micronuclei increased (400 and 500 mg L−1). [ABSTRACT FROM PUBLISHER]

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. • Purpose of this study is to investigate effect of gadolinium (Gd) content of GdxFe2O3(100-x), (x=0, 5, 10, 15, 20) composite system on structural, thermal, optical and radiation shielding of poly (vinyl alchool) PVA based nanocomposite film. • The characterization of these powders have been obtained by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and Uv–vis spectrometer. • The irradiation properties of 6 MeV energized X-ray via cLINAC to obtain radiation shielding performance. • By using obtained results, the Linear Attenuation Coefficient (LAC), Half Value Layer (HVL), Tenth Value Layer(TVL), Mass Attenuation Coefficient(MAC). • Also, theoretically Zeff values have been calculated. [ABSTRACT FROM AUTHOR]