Effect of Cooling Conditions on Nano-Sized NiFe2O4 Electrical Properties
Nickel ferrite NiFe2O4 nanoparticles have been prepared by sol-gel auto combustion. Two groups of samples were obtained from as-burnt and calcined powders by using various cooling conditions. The X-Ray diffraction (XRD) analyses confirm the single phase spinel structure for all samples. The grain sizes investigated by scanning electron microscopy (SEM) were found within the range of 70-100 nm. DC resistivities for different group of samples are strongly affected by cooling rate, showing the way how to control NiF2O4 electrical properties.
A. Sutka et al., "Effect of Cooling Conditions on Nano-Sized NiFe2O4 Electrical Properties", Advanced Materials Research, Vol. 222, pp. 263-266, 2011