Structure and Mossbauer spectroscopy studies of Ni0.5Zn0.5NdxFe2-xO4 (0.00 ≤ x ≤ 0.10) ferrites

Neodymium (Nd) doped Ni0.5Zn0.5NdxFe2-xO4 (0.00 <= x <= 0.10) ferrites were synthesized by ceramic method. Structure, phase formation and cation distribution is studied by employing X-ray diffraction (XRD), FTIR and Mossbauer spectroscopy. XRD spectra confirm single (spinel cubic) phase in all ferrites. Surface morphology of the ferrites shows uniform distribution of grains with porous surface features. FTIR spectra indicate that the main absorption bands related to tetrahedral and octahedral metal-oxygen bond lying in the range 850-550 cm(-1). Room temperature transmission Mossbauer spectra show weak doublet peak which indicate the existence of mixed spinel structure in all ferrites. The hyperfine field (B-hf) at A-sites is negligibly affected by the addition of Nd3+ ions. The average hyperfine field (< B-hf>) at B-sites shows a non-linear variation with increasing Nd-content. This reflects that the Nd3+ ions replace A site Fe3+ ions within spinel lattice. The isomer shift (IS) corresponding to A-site varies more rapidly as compared to B-site. This indicates that the charge distribution of A-site Fe3+ ions is more influenced by Nd3+ ions as compared to charge distribution of B-site Fe3+ ions. The change in Mossbauer parameters with addition of Nd content suggests that the Nd3+ ions preferably replace A site Fe3+ ions, taking the cation distribution form (Zn0.5Fe0.5-xNdx)(A)[Ni0.5Fe1.5](B)O-4 within the spinel lattice.