Structural, electrical and magnetic properties of dilutely Y doped NiFe2O4 nanoparticles

Present study is focused on the structural, electrical and magnetic properties of dilutely Y doped NiFe2O4 nanoparticles. X-ray diffraction confirms the phase formation and shows that samples prepared using sol-gel method exhibit pure spinel phase except that of x = 0.05. Analysis of diffraction pattern and scanning electron microscopy images demonstrate that crystallite as well as particle sizes are increasing with concentration of Y. Presence of impurity phase is further confirmed by Raman measurement. There is no significant change in vibrational modes up to the solubility limit (x = 0.03), however, these modes are shifted towards higher wavenumber for 5% Y doped Ni ferrite due to impure phase. Incorporation of dilute amount of Y ions in host lattice results in an enhancement in the saturation magnetization, coercivity and resistivity. The enhanced saturation magnetization and resistivity is understood on the basis of exchange interactions induced by the substitution of Y3+ ions for Fe3+ ions at B-site.