| Summary: | Nanosize NiFe2O4 was prepared by template method and precipitation process
using same starting materials. The use of soluble starch in both synthesis
routes was investigated. The amount of the used precipitating agent (Na2CO3)
for the precipitation approach was selected according to two adopted
scenarios based on theoretical and average yield of possible side reaction
expressed by the degree of substitution (DS). The results of SEM
microstructural analysis of the prepared Niferrite powders demonstrate
evident influence of the applied preparation method whereas
high-magnification FE-SEM images show very similar fine-grained structures
characterized by different size of particles. According to the results of XRD
analysis, the obtained ferrite powders exhibit only slight differences in
phase composition with calculated crystallite size for template sample dXRD =
36 nm and for the both precipitation route samples dXRD = 21 nm. Additional
sample characterization using 57Fe Mössbauer spectroscopy supports the
findings of the microstructural and XRD analysis. The “clearest” spectrum was
obtained for the template sample while the strongest influence of
nanocrystalline component was observed for the sample prepared with maximal
amount of precipitation agent (DS=3). The room temperature magnetic
hysteresis loops, recorded using vibrating sample magnetometer (VSM), are
very similar and exhibit characteristic shape with values of magnetic
properties within expected range for this type of material. [Projekat
Ministarstva nauke Republike Srbije, br. OI 172037 i br. TR34023]
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