Details

Autor(en) / Beteiligte

• Kalyana Lakshmi, Y.
• Bharadwaj, S.
• Chanda, Swathi
• Venkata Koti Reddy, Ch
• Pola, Someshwar
• Siva Kumar, K.V.

Titel

Iron ion non-stoichiometry and its effect on structural, magnetic and dielectric properties of cobalt ferrites prepared using oxalate precursor method

Ist Teil von

• Materials chemistry and physics, 2023-02, Vol.295, p.127172, Article 127172

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2023

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• Cobalt ferrites with compositional formula CoFe2±xO4 (x = 0, ±0.1) was synthesized by oxalate precursor method and the precursor powders were sintered at 1150 °C. X-ray diffraction studies confirm a single phase cubic spinel structure with Fd3‾ m space group. The average grain sizes are found to vary between 0.4 and 0.7 μm. The highest saturation magnetization was observed for the stoichiometric cobalt ferrite sample with 87.7emu/g but it reduced significantly to 77.7 emu/g for the iron excess sample. The cation distributions in these samples were understood using Néel sub-lattice model. Coercivity improved for excess iron cobalt ferrite sample but appreciably reduced for the iron deficient cobalt ferrite sample. Iron deficient sample exhibits an increase in dielectric constant which has been attributed to variation in Co3+/Fe2+ ions in octahedral sites. •Cobalt and iron ion occupancy in octa and tetrahedral sites is estimated using Neel sub-lattice model.•Cation distribution was further verified by Rietveld and X-ray photoelectron spectroscopy (XPS) analysis.•Small dispersion peak ∼120 kHz in all samples is a characteristic of magneto-mechanical frequency of the cobalt ferrite.