A new concept for preparing hollow metal oxide nanopowders by salt-assisted spray pyrolysis applying nanoscale Kirkendall diffusion is introduced. The composite powders of metal oxide and indecomposable metal salt are prepared by spray pyrolysis. Post-treatment under a reducing atmosphere and subsequent washing using distilled water produce aggregation-free metal nanopowders. The metal nanopowd...

in this work, mn ferrite nanopowders were prepared by co-precipitation method and were characterized. phase identification of the nanopowders was performed by x-ray diffraction method and the mean particle size of the nanopowders was calculated by scherrer's formula, using necessary corrections. magnetic parameters of the prepared nanopowders were measured by a vibrating sample magnetomete...

In the Present work structural, morphological and compositional properties of ZnO nanopowders synthesized using Zinc nitrate and NaOH using sol-gel process were reported. The synthesized nanopowders were further analyzed using X-Ray Diffraction (XRD), Scanning electron microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopic characterizations. Crystalline size and Lattice strain det...

Gas sensing properties of metal oxide nanopowders (ZnO, TiO2, WO3, SnO2) with average diameters of 40-60 nm were analyzed by room-temperature photoluminescence spectroscopy. The influence of gas environment (O2, N2, H2, CO, CO2) on the emission intensity was investigated for metal oxide nanopowders with surface doped by impurities (Pt, Ag, Au, Sn, Ni or Cu). Established physicochemical regulari...

A technique of determination of complex permittivity and permeability of ferrimagnetic nanopowders using S-parameter measurements in rectangular waveguide and results of its study are presented in this paper. The permittivity and permeability of the ferrimagnetic nanopowders are determined by the novel technique in which magnitudes of S-parameters are used only. Use of the technique allows to s...

Electrical explosion of wires (EEW) is a method for production of nanopowders. Depending on type of chemical composition of working ambient in the discharge chamber nanopowders of carbides can be produced (EEW in hydrocarbons) or nanopowders of oxides (EEW in oxygen contained medium). Phase compositions of nanopowders prepared by electrical explosion of tungsten and aluminium wires in liquid an...

In order to synthesize Bi2Se3 nanopowders by a solvothermal synthesis method, ethylenediamine, dimethylformamide, acetone, absolute ethanol, and deionized water were respectively used as a solvent, using BiCl3 and elemental Se powders as starting materials and KBH4 as a reductant at 180 C for different times. X-ray diffraction was used for examining the phase composition of the products. The re...

In the present paper the sintering behavior of 3 mol% yttria-stabilized zirconia (3Y-TZP) with and without small amount (0.2 wt %) of SiO2 additive was investigated. It has been studied the silica impact which was added in two ways (co-precipitation and mechanical mixing) on sintering kinetics of 3Y-TZP nanopowders at the initial sintering stage. It was found the silica additive leads to the ch...

The corrosion resistance of nanopowders of borides and carbides of metals of IV-VIB groups, as well as of silicon carbide, was studied in the standard nickeling electrolytes. As objects of study, nanopowders with the content of the main phase 91.8-97.6% and with the average particle size 32-78 nm were used. Their corrosion resistance was evaluated depending on the acidity of the electrolyte, te...

In this study, the effects and interactions of reaction time and capping agent assistance during sol-gel synthesis of magnesium substituted hydroxyapatite nanopowder (MgHA) on hydroxyapatite (HA) to β-tricalcium phosphate (β-TCP) ratio, Ca/P ratio and mean crystallite size was examined experimentally as well as through statistical analysis. MgHA nanopowders were synthesized by sol-gel technique...