Inverse spinel ZnFe2O4 nanoparticles synthesized by ion implantation and post-annealing: An investigation using X-ray spectroscopy and magneto-transport

Noncrystalline ZnFe2O4 has been investigated intensively due to the drastic difference in cation distribution compared with bulk materials. We previously synthesized ZnFe2O4 nanoparticles by ion implantation and post-annealing [S. Zhou, K. Potzger, H. Reuther, G. Talut, F. Eichhorn, J. von Borany, W. Skorupa, M. Helm, J. Fassbender, J. Phys. D - Appl. Phys. 40 (2007) 964]. These ZnFe2O4 nanocrystals are crystallographically oriented inside the ZnO matrix and show a hysteretic behavior upon magnetization reversal at 5 K. Their magnetic properties are explained by assuming that Fe3+ ions partially occupy tetrahedral sites. In this paper an X-ray spectroscopic and magneto-transport investigation on ZnFe2O4 nanocrystals in a ZnO matrix will be presented. The occupation of Fe3+ at tetrahedral sites has been directly proved. A positive magneto resistance (MR) effect is observed and is attributed to ordinary MR. (C) 2009 Elsevier B.V. All rights reserved.