Structural, magnetic and hyperfine characterization of zinc-substituted magnetites

Nanosized Fe3 − xZnxO4 powders were synthesized by co-precipitation and characterized by total chemical analysis, X-ray diffraction, magnetic susceptibility and Mössbauer spectroscopy. The results showed that, for x ≤ 0.15, the as-prepared samples are mostly zinc-substituted magnetites but have maghemite as a minor phase. For x ≥ 0.30, only the Fe3 − xZnxO4 solid solution is found. Increasing the zinc content from the end concentration x = 0, increases the lattice parameter but smaller become the mean crystalline diameter and the magnetic susceptibility. In addition, the magnetic hyperfine fields of the iron sites in the spinel structure, A and B, decrease up to collapse at x ≤ 0.90.