Details

Autor(en) / Beteiligte

• Bhandare, S.V.
• Kumar, R.
• Anupama, A.V.
• Choudhary, H.K.
• Jali, V.M.
• Sahoo, B.

Titel

Annealing temperature dependent structural and magnetic properties of MnFe2O4 nanoparticles grown by sol-gel auto-combustion method

Ist Teil von

• Journal of magnetism and magnetic materials, 2017-07, Vol.433, p.29-34

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2017

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Phase pure MnFe2O4 samples were prepared by sol-gel auto-combustion method.•Annealing MnFe2O4 below ∼500°C, two spinel phases were observed indicating partial oxidation of Mn2+ to Mn3+.•Oxidation of Mn2+ to Mn3+ results in decrease in lattice parameter of the spinel lattice.•Annealing at ≥ 600°C, MnFe2O4 decomposes into crystalline α-Mn2O3 and α-Fe2O3 along with amorphous-FeO phase. Manganese ferrite (MnFe2O4) nanoparticles were synthesized by sol-gel auto-combustion method using manganese nitrate and ferric nitrate as precursors and citric acid as a fuel. Scanning electron micrographs show irregularly shaped morphology of the particles. The as-prepared samples were annealed at 400, 500, 600 and 800°C for 2h in air. The phase identification and structural characterizations were performed using powder X-ray diffraction technique along with Mössbauer spectroscopy. Magnetization loops and 57Fe Mössbauer spectra were measured at RT. After annealing the sample at or below ∼ 500°C, we observed two different spinel phases corresponding to two different lattice parameters. This is originating due to the partial oxidation of Mn2+ to Mn3+. At high annealing temperatures (∼ 600°C or above) the spinel MnFe2O4 phase decomposes into crystalline α-Mn2O3 and α-Fe2O3 phases, and amorphous FeO phase.