Significant reduction of saturation magnetization and microwave-reflection loss in barium-natural ferrite via Nd3+ substitution

Highlights: • Incorporation of Nd³⁺ ions into barium-natural ferrite (BNFs) via the modified solid-state reaction method. • Role of Nd³⁺ ions in modifying structural and magnetic properties of the BNFs. • Significant reduction of microwave-reflection loss in the x-band. To minimize the signal degradation, many electronic devices require efficient microwave absorbers with very low reflection-losses within the X-band. We prepared a series of trivalent neodymium-ion (Nd³⁺) substituted barium-natural ferrite using a modified solid-state reaction method. The effect of the Nd³⁺-ion content on the structure, surface morphology, magnetic properties, and microwave reflection loss was studied. The composites were characterized using X-ray diffraction, a vibrating sample magnetometer, scanning electron microscopy, and a vector network analyzer. The XRD patterns of the sample without Nd³⁺ reveal the presence of BaFe₁₂O₁₉ (hexagonal) and BaFe₂O₄ (rhombohedral) phases. Furthermore, a new hexagonal crystal phase of Ba₆Nd₂Fe₄O₁₅ appeared after substituting Nd³⁺. The average size of the prepared barium-natural ferrite particles was estimated to be between 0.4 and 0.8 μm. Both saturation magnetization and microwave reflection losses of these barium-ferrites were significantly reduced by increasing the Nd³⁺ content.