An optimal low-temperature tartrate precursor method for the synthesis of monophasic nanosized ZnFe2O4
In this study, the synthesis of monophasic nanocrystalline zinc ferrite (ZnFe2O4) was achieved by controlling the thermal decomposition conditions of a zinc–iron tartrate precursor method. Differential thermal analysis/thermogravimetry (DTA/TG), X-ray diffraction (XRD), Fe2+ content analysis, transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) techniques were used to investigate the effect of heat treatment conditions on the calcined powders. The thermal decomposition of the precursor led to an intermediate phase formation of ZnO, Fe3O4, and γ-Fe2O3. It was found that the Fe3O4 → γ-Fe2O3 oxidation reaction is the key step in producing monophasic nanosized ZnFe2O4. The monophasic nanoparticles of ZnFe2O4 can be obtained when the precursor is heat treated under a low temperature (300–400 °C) and long residence time (4 h) process that can prompt the Fe3O4 oxidation and prevent the formation of α-Fe2O3.
KeywordsZinc ferrite Iron oxide Spinel Nanoparticles Fe3O4 Thermal processing
- Kester E, Perriat P, Gillot B, Tailhades Ph, Rousset A (1997) Correlation between oxidation states of transition metal ions and variation of coercivity in mixed-valence defect spinel ferrites. Solid State Ionics 101–103:457–463Google Scholar
- Rane KS, Verenkar VMS, Sawant PY (1999) Hydrazine method of synthesis of γ-Fe2O3 useful in ferrites preparation. Part IV—preparation and characterization of magnesium ferrite, MgFe2O4 from γ-Fe2O3 obtained from hydrazinated iron oxyhydroxides and iron (II) carboxylatohydrazinates. J Mater Sci Mater Electron 10:133–140CrossRefGoogle Scholar
- Vogel I (1961) A textbook of quantitative inorganic analysis. Longmans, New York, p 308Google Scholar