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Fine particles n(MnO)/(1 − n)ZnO (n = 0.05 to 0.95) were prepared by wet chemistry method. According to X-ray diffraction analysis the obtained samples with n = 0.95, 0.90, 0.80, 0.70, 0.60 contained Mn3O4 and ZnMn2O4 phases, while samples with n = 0.05, 0.10, 0.20, 0.30, 0.40 and 0.50 contained ZnMnO3 and ZnO phases. The mean crystalline size of ZnMnO3 varied from 8 to 13 nm. The magnetic resonance investigations have been carried out at room temperature. Slightly asymmetric, broad and intense magnetic resonance line is recorded for all samples. The magnetic resonance spectra parameters showed marked differences depending on the composition index n. This could be explained by the variation of the magnetic susceptibility and a much slower evolution of spin relaxation, associated with the interaction of crystal field and superexchange interactions. Taking into account the values of magnetic resonance parameters, the investigated samples could be divided into two groups: these with the composition index n 0.50. A detailed discussion of the magnetic properties of different phases in the n(MnO)/(1−n)ZnO system is presented.

Nanocrystalline samples of ZnO(Fe) were synthesized by wet chemical method. Samples were characterized by X-ray diffraction to determine composition of the samples (ZnO, Fe2O3, ZnFe2O4) and the mean crystalline size (8–52 nm). In this paper we report the experimental spectra of the Raman scattering (from 200 to 1600 cm−1). Main characteristics of experimental Raman spectrum in 200 to 1600 cm−1 spectral region are: sharp peak at 436 cm−1 and broad two-phonon structure at ≈ 1150 cm−1, typical of ZnO; broad structure below 700 cm−1 that has different position and shape in case of ZnFe2O4 or Fe2O3 nanoparticles. PACS numbers: 63.20.−e, 78.30.Fs, 78.67.−n

Nanocrystalline samples of ZnO doped with Fe2O3 were synthetized by wet chemical method. The series of ZnO nanosized samples in the wide range of Fe2O3 concentration (from 5 wt.% to 95 wt.%) was prepared by precipitation from nitrate solutions using ammonia. The phase composition of the samples was determined using X-ray diffraction measurements. The phases of hexagonal ZnO, and/or rhombohedric Fe2O3, and/or ZnFe2O4 were identified. The mean crystalline size of nanocrystals, determined with the use of Scherrer’s formula, varied from 8 to 52 nm. The preliminary micro-Raman spectroscopy measurements were performed. The observed features are typical of Fe doped ZnO nanoparticles. The magnetic measurements revealed the presence of different types of magnetic behavior. For samples with high Fe2O3 contents (above 70 wt.%) the ferromagnetic ordering was observed at room temperature. For samples with lower Fe2O3 contents we observed the phenomenon of superparamagnetism above the blocking temperature.

FourseriesofZnOnanopowdersobtainedbyamicrowavehydrothermalmethodareexamined. Twodifferentsolvents (ethanol and distilled water) and different values of pressure during heating in the reactor were used.The obtained nanopowders show a bright emission covering visible light spectral region, including the bandedge emission. Results of scanning electron microscopy, X-ray diffraction, photo- and cathodoluminescenceinvestigationsandalsoCIE1961chromaticitydiagramarepresented.PACS:78.67.

R. Kostic, N. Romcevica,∗, M. Romcevic, B. Hadžic, R. Rudolf, I. Kuryliszyn-Kudelska, W. Dobrowolski, U. Narkiewicz and D. Sibera Institute of Physics, Pregrevica 118, 11080 Belgrade, Serbia Faculty of Mechanical Engineering, University of Maribor, Smetanova 17, 2000 Maribor, Slovenia Zlatarna Celje d.d., Kresnikova 19, 3000 Celje, Slovenia Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warszawa, Poland Szczecin University of Technology, Institute of Chemical and Environment Engineering