Influence of Nd-NbZn co-substitution on structural, spectral and magnetic properties of M-type calcium-strontium hexaferrites Ca0.4Sr0.6-xNdxFe12.0-x(Nb0.5Zn0.5)xO19

This is first report on Nd-NbZn co-substituted M-type Ca-Sr hexaferrites with nominal compositions Ca0.4Sr0.6-xNdxFe12.0-x(Nb0.5Zn0.5)(x)O-19 (x = 0.00-0.32) fabricated by the conventional solid-state reaction method. X-ray diffractometer (XRD), Fourier transformer infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM), physical property measurement system-vibrating sample magnetometer (PPMS-VSM) were employed to characterize M-type calcium-strontium hexaferrites. XRD patterns of the hexaferrites with Nd-NbZn content (x) of 0.00 <= x <= 0.16 showed the single M-type patterns of the hexaferrites with Nd-NbZn content (x) >= 0.24, the impurity phase (alpha-Fe2O3) was observed. FT-IR frequency bands in the range (592-613) cm(-1) and (430-470) cm(-1) corresponded to the formation of tetrahedral and octahedral clusters of metal oxides in the hexaferrites, respectively. FE-SEM micrographs showed that the grains were platelet-like shapes. The saturation magnetization (M-s) and magneton number (n(B)) decreased with increasing Nd-NbZn content (x) from 0.00 to 0.32. The remanent magnetization (M-r) first increased with Nd-NbZn content (x) from 0.00 to 0.08, and then decreased when Nd-NbZn content (x) >= 0.08. The M-r/M-s ratio, coercivity (H-c) and magnetic anisotropy field (H-a) increased with increasing Nd-NbZn content (x) from 0.00 to 0.32. First anisotropy constant (K-t) first slightly increased with Nd-NbZn content (x) from 0.00 to 0.08, and then decreased when Nd-NbZn content (x) >= 0.08. (C) 2018 Elsevier B.V. All rights reserved.