Structural, magnetic, and microwave absorption properties of SrCexFe12-xO19/PVP composites

Ce-substituted strontium hexagonal M-type SrCexFe12-xO19 ferrites (x = 0.0, 0.03, 0.05, 0.07, and 0.1) and various concentrations of poly(N-vinilpyrrolidone) (PVP) polymer were prepared by citrate sol-gel auto-combustion route, and their structural and magnetic properties were studied. The Fourier transform infrared spectroscopy (FT-IR) revealed bands at 437, 549, and 598 cm(-1), related to the stretching vibrating bonds of Fe-O. The X-ray diffraction analysis (XRD) showed that in all samples, the SrFe12O9 phase is completely formed, and the peaks are taken with the standard card (JCPDS 01-084-1531) correspond to the type of strontium hexaferrite with the P63/mmc space group. Field emission scanning electron microscopy (FESEM) analysis revealed the hexagonal like the shape of all samples. Vibrating sample magnetometer (VSM) results showed ferromagnetic nature for all the specimens. By increasing the dopants content, coercivity (H-c) and saturation magnetization (M-s) erratically changed but H-c decreased with increasing PVP amount. The complex permittivity, complex permeability and microwave absorption properties of the resulting powder were measured in the range of 8-13 GHz.