Advances in M-type Hexaferrites: A review tailoring structural, magnetic, and microwave absorption properties for emerging technologies
Pramod D. Mhase, Varsha C. Pujari, Sagar E. Shirsath, Akash V. Fulari, Santosh S. Jadhav, C.V. Ramana, Sunil M. Patange
Abstract
This review provides a comprehensive analysis of M-type hexaferrites , with emphasis on synthesis strategies, cation substitution effects, and property optimization for applications in EMI shielding , microwave absorption, and spintronics . Trends in structure–property relationships are discussed, along with future challenges and directions in material design. M-type hexaferrites are recognized for their unique attributes, including high magnetic anisotropy , chemical stability, and performance efficiency in high-frequency domains. This article examines the influence of various synthesis techniques, such as solid-state, sol-gel auto-combustion, hydrothermal, and co-precipitation methods, on the physical and functional properties of these materials. Special attention is given to the role of cation substitution and doping strategies in optimizing electrical, magnetic, and microwave absorption characteristics for applications including electromagnetic interference shielding, stealth technology, radar systems, antenna design , and energy storage. Advanced characterization methods, such as X-ray diffraction, Mössbauer spectroscopy , and electron microscopy , are discussed to elucidate the mechanisms driving property enhancements, such as improved coercivity , reduced dielectric loss , and broader absorption bandwidths. This review also highlights the interplay between crystal lattice dynamics, magnetic domain interactions, and defect engineering, with insights into emerging applications in spintronics, high-frequency devices, and optoelectronics . Current challenges in synthesis parameter optimization and material design are addressed, and future research directions are proposed, emphasizing the potential of M-type hexaferrites in next-generation industrial, medical, and communication technologies. This comprehensive study aims to serve as a guide for advancing the multifunctional capabilities of M-type hexaferrites to meet the evolving demands of modern technology.