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A series of Co 0.6 Zn 0.4 Pr x Fe 2−x O 4 (x=0.0, 0.025, 0.05, 0.075, 0.10) spinel ferrites was successfully synthesized by conventional ceramic technique. X-ray Diffraction (XRD) showed that along with spinel phase, secondary phase (PrFeO 3 ) was appeared for composition with x≥0.075. Scanning Electron Microscopy (SEM) of the samples showed inhomogeneous grain size distribution. Electrical measurements showed that the resistivity and activation energy increased with the praseodymium (Pr 3+ ) substitution while dc resistivity decreased with the temperature, showing the semiconductor behavior of the synthesized samples. Remanence (M r ) and the saturation magnetization (M s ) showed decreasing trend while coercivity (H c ) increased with the substitution of Pr 3+ into Co-Zn spinel ferrites. The anisotropic constant K 1 exhibited similar behavior as H c , showing their interdependence and it also showed that anisotropy enhanced with the substitution of praseodymium. The above-mentioned parameters suggested that the synthesized samples might be suited for the application of high density magnetic recording. [ABSTRACT FROM AUTHOR]

High-frequency nanocomposites have gained attention as electronic and telecommunication technologies. These nanocomposites consist of ferrite and a polyaniline matrix. Sol-gel technique was used to generate the ferrite nanomaterial, and in-situ synthesis was used to generate the polyaniline. The X-ray diffraction (XRD) analysis elucidated the existence of a single-phase structure comprising SrEr 0.04 Fe 1.96 O 4 ferrite particles dispersed throughout the polyaniline matrix. To counteract the amorphous nature of polyaniline, adding spinel ferrite to nanocomposites boosted their crystallite size (20 nm–56 nm). When ferrite was combined with polyaniline, the dielectric constants and dielectric loss (ε ′ , ε ″) were found to decrease as a function of frequency. The ferromagnetic characteristics of the manufactured composites were discovered through hysteresis loop analysis. Saturation Ms, remanence Mr, and coercivity Hc all increased with ferrite content. Direct current (dc) resistivity and activation energies of the composite sample enhanced with concentration of polyaniline in ferrites. Improvements in all the properties of nanocomposites (FP4) may be suitable candidates for high frequency applications. [ABSTRACT FROM AUTHOR]

Spinel ferrites with configuration Co 1-x Ba x Fe 2 O 4 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) were created by sol-gel technique. X-ray diffraction pattern showed that the entire specimen possessed singular phase. The standards of lattice constant increased, while densities as well as porosity decreased with the increment of barium ions. The room temperature resistivity and activation energy increased with the addition of barium ions. The temperature dependent resistivity presented the decreasing trend with the increase of barium ions which proves its semiconducting nature. The magnetization decreased while coerecivity was increased with the substitution of barium ions, as applied field changed from −2 KOe to +2 KOe. Dielectric properties were also measured from 3 MHz to 1 G Hz. Due to high value of dc resistivity and low dielectric loss, these samples might be suitable for high-frequency devices. [ABSTRACT FROM AUTHOR]