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Hydrothemal conversion of lanthanide/actinide oxalate salts to nanocrystalline oxide has gained technological importance in the chemistry of f-elements. Herein, we present a study describing the mechanism behind the hydrothermal recrystallization and decomposition of cerium (and Ce-Gd) oxalate to oxide. Structural determination of all intermediate nanocrystalline products was possible thanks to three-dimensional electron diffraction. This work reveals the enormous structural abilities of simple oxalate ligands. [ABSTRACT FROM AUTHOR]

Nickel oxide (NiO) nanoparticles were synthesized by a rapid method and well characterized. The nanoparticles were then used with graphite powder to prepare modified carbon paste electrode (CPE/NiO) for electrocatalytic oxidation of paracetamol (AC). The CPE/NiO showed higher electro catalytic activity than nickel rod electrode in electrocatalytic oxidation of AC in alkaline media. The assay of AC, mechanism and kinetics of the electrooxidation process were investigated by cyclic voltammetry and chronoamperometry. The catalytic rate constant and the charge transfer coefficient of AC electrooxidation by the active nickel species and the diffusion coefficient of AC were also reported. The linear dependence of the peak current on the concentration of the AC was observed in the range 2-14 mM. This procedure was successfully applied to the determination of AC in tablets. The results showed sufficient precision, accuracy and achieved a mean recovery of 97.2% (RSD = 6.7%). Keywords: paracetamol, electrocatalytic oxidation, carbon paste electrode, NiO nanoparticles, voltammetry DOI: 10.1134/S1061934817070024, NiO has been extensively investigated as an important transition metal oxide. It finds a wide range of applications in various fields, such as catalysis [1, 2], electric batteries [3, 4], [...]

Nickel ferrite nanoparticles prepared by a microwave-assisted autocombustion method with different fuels and microwave powers were used as bare adsorbents for 2-nitrophenol removal from aqueous solutions. Characterization of the as-prepared samples revealed a fundamental variety with respect to their size and surface area. Meanwhile, the crystal phase, functional groups, surface polarity, and magnetic properties remained almost the same. After electing the most efficient adsorbent based on batch experiments, pH influence was established and optimized. Afterward, equilibrium studies were conducted. The kinetic models and adsorption isotherms further facilitated a better understanding of the adsorption mechanism that comprised mainly the multilayered condensation of 2-nitrophenol molecules through the hydrogen bonding. [ABSTRACT FROM AUTHOR]

ZnO- nanoparticles with an average particle size of 24 nm were successfully synthesized using the microwave assisted sol- gel technique. Structural and morphological properties of the nanoparticles were characterized by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Energy disperse spectrum (EDS) and Fourier transform infrared spectroscopy (FTIR). The band gap energy was measured to be 3.27 eV. The photocatalytic degradation of tartrazine has been studied in aqueous solution under UV-C irradiation at different pH values, catalyst doses, and tartrazine concentration. Degradation of samples was monitored by a spectrophotometer. Results have shown that 95% of 50 mg L-1 tartrazine was degraded in 120 min due to the photocatalytic degradation in presence of 0.02 g of ZnO-nanoparticles. The photocatalytic degradation kinetics has also been investigated. The experimental data were fitted very well in the pseudofirstorder kinetic and Langmuir-Hinshelwood models. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis and characterization of CdS nanoparticles for investigation of photocatalytic degradation of 2, 4, 6-Trichlorophenol CdS nanoparticles were synthesized by microwave-assisted sol-gel method. Nano particles was characterized by various techniques such as X-ray diffraction, filed emission scanning electron microscopy, energy dispersive spectroscopy, fourier transform infrared spectroscopy and UV-visible spectroscopy. The average crystallite size was found to be 46 nm. The influences of catalyst amount, contaminant concentration and pH of the reaction solution were evaluated and optimized. After photocatalytic degradation, the remained of 2, 4, 6-Trichlorophenol was measured by UV-vis spectrophotometer. In the optimum condition, the highest degradation was obtained 90% after 3hours UV-C light irridiation. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanoparticles were synthesized, characterized, and used for photocatalytic removal of amoxicilline and sulfamethoxazole from contaminated water. Microwave-assisted gel combustion synthesis method was optimized for type and amount of complexing agent and calcination temperature, in order to obtain the best photocatalytic activity. Characterization of ZnO nanoparticles according to their scanning electron microscopy and transmission electron microscopy images and X-ray diffraction pattern showed homogenous spherical nanoparticles with an average crystalline size of 25.82 nm. Effects of several operational factors such as pH of antibiotic solution, initial concentration of antibiotic, ZnO nanoparticles loading amount, and presence of NaCl salt or buffered solution were investigated. Results showed complete removal of antibiotic compounds in six hours using ZnO nanoparticles/UV-C irradiation. Mineralization of organic content were 62.8 and 20.8% for amoxicilline and sulfamethoxazole, respectively. Photocatalytic removal of both antibiotics followed the Langmuir–Hinshelwood model in the range of concentration of 5–20 mg L−1. ZnO nanoparticles were used for three subsequent runs without significant decrease in their photocatalytic activity. [ABSTRACT FROM PUBLISHER]

ZnO nanoparticles were manufactured using microwave-assisted combustion. The structural and morphological properties of the nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. Photocatalytic degradation of ortho-nitrophenol (O-NP) in aqueous solution using the synthesized nanoparticles was performed under UV–C irradiation and is reported for the first time. The effect of the initial O-NP concentration, amount of photocatalyst, pH, and salt was investigated during photodegradation. Analysis of the degraded samples using HPLC with UV detection revealed that photocatalysis in the presence of ZnO nanoparticles removed 98% of the O-NP in 5 h. In addition, the photocatalytic degradation kinetics of O-NP were studied, and the results suggest that the data are best fitted to pseudo-first-order kinetic and Langmuir–Hinshelwood models. [ABSTRACT FROM PUBLISHER]