The effects of annealing on the magnetic properties of nanocrystalline ZnFe2O4 have been studied. The as-prepared sample ZnFe2O4 with the particle size of about 3 nm presents a relatively low blocking temperature of about 6 K as derived from the peak of the zero-field-cooled curve measured in a SQUID. Under the effect of annealing, the particle size significantly increases. Up to the annealing temperature of 800°C, the blocking temperature is found to increase with increasing particle size, whereas the (effective) anisotropy constant KA decreases. The latter effect is attributed to the smaller contribution of the surface anisotropy when the particle size increases.
- Magnetic properties
- Nanocrystalline zinc ferrite