کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1408426 1501741 2014 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structural, magnetic, dielectric and optical properties of nickel ferrite nanoparticles synthesized by co-precipitation method
ترجمه فارسی عنوان
خواص ساختاری، مغناطیسی، دی الکتریک و نوری نانوذرات فریت نیکل سنتز شده توسط روش هم بارگیری
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
چکیده انگلیسی


• NiFe2O4 nanoparticles were synthesized by a co-precipitation method.
• Raman spectroscopy indicates mixed spinel structure for NiFe2O4.
• M–H loops and ESR spectra suggested strong surface effects in the nanoparticles.
• Photoluminescence study indicates that Ni2+ ions occupy both tetrahedral and octahedral sites.

Nickel ferrite nanoparticles were synthesized by wet chemical co-precipitation method and the corresponding temperature dependent structural, magnetic and optical properties of these nanoparticles have been investigated. X-ray diffraction patterns show the single phase cubic spinal crystal structure belonging to the space group Fd3m. The average crystallite size varies in the range 8–20 nm with varying sintering temperature. Raman spectroscopy exhibits a doublet-like peak behaviour which indicates the presence of mixed spinel structure. The saturation magnetization, coercivity and remanence increase with increasing sintering temperature from 250 to 550 °C. The non-saturation and low values of magnetization at high fields indicate the strong surface effects to magnetization in NiFe2O4 nanoparticles. The g-value calculated from electron spin resonance spectrum indicates the transfer of divalent metallic ion from octahedral to tetrahedral site (i.e. mixed spinel structure). The dielectric permittivity, loss tangent and ac conductivity measurements show strong temperature dependence at all frequencies. The observed ac conductivity response suggests that the conduction in ferrite nanoparticles is due to feeble polaron hopping between Fe3+/Fe2+ ions. Room temperature UV–vis diffuse spectra indicate that NiFe2O4 is an indirect band gap material with band gap ranges from 1.27 to 1.47 eV with varying sintering temperature. The photoluminescence study clearly indicates that the Ni2+ ions occupy both octahedral and tetrahedral sites confirming mixed spinel structure.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure - Volume 1076, 5 November 2014, Pages 55–62
نویسندگان
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