M. Ebrahimi, S. A. Seyyed Ebrahimi, S. M. Masoudpanah,
Volume 14, Issue 1 (March 2017)
Abstract
In this work, the effects of co-precipitation temperature and post calcination on the magnetic properties and photocatalytic activities of ZnFe2O4 nanoparticles were investigated. The structure, magnetic and optical properties of zinc ferrite nanoparticles were characterized by X-ray diffraction (XRD), vibrating sample magnetometry and UV–Vis spectrophotometry techniques. The XRD results showed that the coprecipitated as well as calcined nanoparticles are single phase with partially inverse spinel structures. The magnetization and band gap decreased with the increasing of co-precipitation temperature through the increasing of the crystallite size. However, the post calcination at 500 °C was more effective on the decreasing of magnetization and band gap. Furthermore, photocatalytic activity of zinc ferrite nanoparticles was studied by the degradation of methyl orange under UV-light irradiation. Compare with the coprecipitated ZnFe2O4 nanoparticles with 5% degradation of methyl orange after 5 h UV-light light radiation, the calcined ZnFe2O4 nanoparticles exhibited a better photocatalytic activity with 20% degradation.
B. Pourgolmohammad, S.m. Masoudpanah, M.r. Aboutalebi,
Volume 15, Issue 2 (June 2018)
Abstract
In this work, the different fuels (citric acid, glycine and urea) were used for solution combustion synthesis of CoFe2O4 powders. X-ray diffraction, Raman spectroscopy, electron microscopy and vibrating sample magnetometry techniques were employed for characterization of phase evolution, cation distribution, microstructure and magnetic properties of the as-combusted CoFe2O4 powders. Single phase CoFe2O4 powders with partially inverse structure in which the Co2+ cations are distributed in both tetrahedral and octahedral sites were synthesized by the citric acid, glycine and urea fuels. The as-combusted CoFe2O4 powders by the citric acid fuel exhibited the highest inversion coefficient. The crystallite size of the as-combusted CoFe2O4 powders synthesized by urea fuel was 15 nm, increased to 41 and 52 nm for the glycine and citric acid fuels, respectively. Furthermore, the solution combusted CoFe2O4 powders showed ferromagnetic behavior with saturation magnetization of 61.9, 63.6 and 41.6 emu/g for the citric acid, glycine and urea fuels, respectively. The high crystallinity and particle size of the as-combusted CoFe2O4 powders using glycine fuel led to the highest magnetization and the moderate coercivity.
