Synthesis and characterization of Dy3Fe5O12 nanoparticles fabricated with the anion resin exchange precipitation method

Dysprosium-iron garnet (DyIG) nanoparticles were synthesized with the new modification of the anion resin exchange precipitation method. Fourier transform infrared spectroscopy, X-ray diffraction, and transmission electron microscopy showed nanoparticles to be of the garnet structure with an excellent crystallinity. Magnetic properties were studied by using QUANTUM Design MPMS-XL system and the visible magnetic circular dichroism (MCD). Nanoparticles magnetic properties were close to those of bulk DyIG crystals. Dependence of the nanoparticles magnetization (M) on the external magnetic field (H) is described by a narrow hysteresis loop in relatively low fields and the strong linear M increase with the further H increase. The visible MCD of DyIG was studied in this work for the first time. The MCD spectra consisted of several peaks associated with electron transitions in iron and dysprosium ions located in different spectral intervals. Dependences of the MCD peak intensities on temperature and magnetic field were studied

Synthesis of gelatin-stabilized concentrated hydrosols of copper nanoparticles

В работе изучено влияние реакционных условий (концентраций сульфата меди, гидразина, желатина, твердости желатина по Блуму, рН и температуры синтеза) на процесс формирования наночастиц меди при восстановлении сульфата меди (II) раствором гидразина. Найдены условия формирования устойчивых к окислению и агрегации концентрированных (0,4 М) гидрозолей металлической меди. По данным ПЭМ, полученные гидрозоли содержат сферические наночастицы металлической меди размером 30-60 нм, стабилизированные 2-3 нм слоем желатина

Synthesis of gelatin-stabilized concentrated hydrosols of copper nanoparticles

В работе изучено влияние реакционных условий (концентраций сульфата меди, гидразина, желатина, твердости желатина по Блуму, рН и температуры синтеза) на процесс формирования наночастиц меди при восстановлении сульфата меди (II) раствором гидразина. Найдены условия формирования устойчивых к окислению и агрегации концентрированных (0,4 М) гидрозолей металлической меди. По данным ПЭМ, полученные гидрозоли содержат сферические наночастицы металлической меди размером 30-60 нм, стабилизированные 2-3 нм слоем желатина

Reactive Ion Exchange Processes of Nonferrous Metal Leaching and Dispersion Material Synthesis

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала

Reactive Ion Exchange Processes of Nonferrous Metal Leaching and Dispersion Material Synthesis

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала

Effect of Polysaccharide Additions on the Anion-Exchange Deposition of Cobalt Ferrite Nanoparticles

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.A facile and rapid method easily reproducible in ordinary laboratory settings is proposed for preparing nanosized cobalt ferrite powders, where the precipitate used is a strongly basic anion exchange resin in the OH form. The effects caused by additions of polysaccharides having various chain natures and various molar weights on the composition, yield, and particle size of the deposition product are studied. Suggested mechanisms underlying these effects are studied. This method makes it possible to appreciably reduce the precursor annealing temperature compared to that in the state-of-art methods for preparing similar oxide systems due to the formation of highly reactive precursors. Optimal conditions are found to prepare stoichiometric precursors such that, once annealed at 600°C, would form a CoFe2O4 pure phase with particle sizes of 10–20 nm. The stability of hydrosols of the thus-prepared cobalt ferrite nanoparticles is studied by dynamic and electrophoretic light scattering. The prepared material is found to be useful for the design of magnetic core–shell hybrid nanostructures. © 2020, Pleiades Publishing, Ltd

ANION-EXCHANGE SYNTHESIS OF COPPER FERRITE POWDERS

Amethod is proposed for synthesizing copper ferrite, consisting in anion-exchange precipitation of copper (II) and iron (III) from solutions of their salts in the presence of tartrate ions as complexing agents followed by calcination of the obtained precipitate. The precursors and the products of their heat-treatment or studied by means of chemical, complex thermal and x-ray phase analyses, IR spectroscopy, scanning electron microscopy, and x-ray spectral microanalysis; the magnetic properties of the obtained samples were also studied. It was determined that a ferromagnetically ordered phase is present in the synthesized materials and their magnetic properties are close to those of bulk CuFe2O4