Synthesis, structure and electromagnetic properties of Mn–Zn ferrite by sol–gel combustion technique

• Published in: Journal of magnetism and magnetic materials 2014-01, Vol.349, p.116-120
• Main Authors: Wang, Wenjie, Zang, Chongguang, Jiao, Qingjie
• Format: Article
• Language: English
• Subjects: Absorbing; Absorbing material; Absorption; Combustion; Complex permeability; Complex permittivity; Composite coating; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric loss; Dielectric loss and relaxation; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; Ferrite; Manganese; Microwave and radio-frequency interactions (excluding resonances); Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other interactions of matter with particles and radiation; Physics; Scanning electron microscopy; Sol gel process
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2013.08.057

The electromagnetic absorbing behaviors of a thin coating fabricated by mixing Mn–Zn ferrite with epoxy resin (EP) were studied. The spinel ferrites Mn1−xZnxFe2O4 (x=0.2, 0.5 and 0.8) were synthesized with citrate acid as complex agent by sol–gel combustion method. The microstructure and surface morphology of Mn–Zn ferrite powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The complex permittivity and complex permeability of the fabricated ferrite/EP composites were investigated in terms of their contributions to the absorbing properties in the low frequency (10MHz to 1GHz). The microwave absorption of the prepared ferrite/EP composites could be tailored by matching the dielectric loss and magnetic loss and by controlling the doped metal ratio. The composites with the ferrite composition x=0.2 are found to show higher reflection loss compared with the composites with other compositions. It is proposed that the prepared composites can potentially be applied in electromagnetic microwave absorbing field. •We designed and synthesized Mn1−xZnxFe2O4 (x=0.2, 0.5 and 0.8), with citrate acid as complex agent by the sol–gel combustion method.•Citrate acid as the complex agent overcomes the aggregation of ferrite resulting in high purity and homogeneous particles.•We investigated the electromagnetic absorbing performance of a fabricated thin coating by introducing Mn–Zn ferrite into epoxy resin (EP).•The Mn0.8Zn0.2Fe2O4 composite coatings could achieve the satisfactory absorbing value of −17dB at 800MHz.•The prepared composites can potentially be used for the application in electromagnetic microwave absorbing field.