Synthesis and characterization of nanocrystallite ZnCrFeO4

Nanocrystallites of spinel ZnCrFcO(4) were synthesized through sol-gel method, and were characterized by X-ray diffractometer (XRD), transmission electron microscopy (TEM), SQUID magnetometer and Mossbauer spectrometer. It is found that the nanocrystallites are spherical and show antiferromagnetism with a higher T-N of 14 K for the sample with diameter of 14 nm and larger magnetic susceptibility than the bulk sample. These are associated with some A ions (Zn2+) and B ions (Fe3+, Cr3+) jumped to each other sites, which therefore enhances both the A-B interaction and B-B interaction. The Mossbauer spectrum of the nanomaterial is different from that of the bulk sample. Additional sextet appears in the Mossbauer spectrum of the nanomaterial except for a doublet. The appearance of the sextet suggests the magnetically ordered state between Fe3+ ions at A and B sites. (C) 2003 Elsevier Science B.V. All rights reserved.