Effect of Sn doping on structural, magnetic and power loss properties of lithium ferrites for high frequency applications

Abstract

The role of Sn doping on the structural, magnetic and power loss properties of Li_0.5+0.5xSn_xFe_2.5-1.5xO₄ ferrites (x = 0.0 to 0.20 in step of 0.05) + 0.5 wt % Bi₂O₃, prepared by solid state technique, has been investigated. X-ray diffraction reveals that Sn ions doped in lithium ferrite up to small concentration. Surface morphology recorded by SEM micrographs illustrates uniform, well connected grain growth in all samples. A small concentration of Sn doping in lithium ferrite improves the grain growth and densification. Magnetic parameters have been evaluated by M − H curves measured at room temperature by VSM. Saturation magnetization was found to be decreasing with Sn concentration in Li_0.5+0.5xSn_xFe_2.5-1.5xO₄ ferrites. In view of applicability of prepared samples for power devices, the magnetic permeability (μ* = μ′-jμ'′) has been recorded in the frequency range of 1 MHz–10³ MHz at room temperature. Further, Power loss response has also been recorded in presence of magnetic induction (B = 10 mT) in frequency range of 50 kHz to 3 MHz. It was depicted a significant reduction in power loss in Sn = 0.05 doped lithium ferrite sample. Reduction in power loss with Sn doping makes it suitable for power applications.