Who should be blinded?

Abstract

The Ni-Zn ferrite/SiO2 nanocomposites (ZNF/SiO2 NCs) with core-shell structure were synthesized using St??ber method and a modified one. The core-shell structure was confirmed by transmission electron spectroscopy (TEM). The product obtained by modified St??ber method was more uniform than by St??ber method. The strength of dipole-dipole interaction between Ni-Zn nanoparticles decreases and the coordination of surface atoms increases due to surface modification. The decrease of blocking temperature and coercivity of the magnetic particles at low temperature can be attributed to the coating of SiO2, which weakens the surface spin disorder of magnetic nanoparticles. ?? 2009 Elsevier B.V. All rights reserved.