高性能铁电吸波材料

铁电材料由于具有高极化以及良好的化学、热稳定性等性质,在微波吸收领域得到了广泛关注。过去二十年,开展了大量关于铁电吸波材料的研究。系统地综述了铁电材料微波吸收的损耗机制与几类典型铁电材料的微波吸收性能。在损耗机制方面,详细论述了铁电材料的电损耗机制,包括介电损耗、电导损耗及界面损耗机制,同时对于多铁材料与铁电-磁杂化复合材料,分析了磁损耗机制以及磁-介电损耗协同机制,并对各类损耗的形成原因及作用机理进行了总结。在微波吸收性能方面,重点阐述了近些年BiFeO3基与BaTiO3基等铁电材料的微波吸收表现,包括单相材料、掺杂材料及复合材料,并对其在室温及高温下的微波吸收性能进行了比较,同时基于材料的结构、微结构与微波吸收强度及有效吸收带宽等参数的演变联系,对其微波响应机制进行了归纳。最后详细分析了影响铁电微波吸收材料发展所面临的关键问题,并对其未来的研究方向进行了展望。

High-performance Ferroelectric Microwave Absorption Materials

Due to high polarization, excellent chemical and thermal stability, ferroelectric materials have attracted great attention of the researcher in microwave absorption field. Many works about ferroelectric microwave absorption materials were reported in the last twenty years. Here, the loss mechanisms and performances of microwave absorption of typical ferroelectric materials are summarized in detail. For the electrical loss mechanisms of ferroelectrics, dielectric loss, electric conductance loss and interface loss mechanism are summarized. For multiferroics and ferroelectric-magnetism hybrid composites, magnetic loss and magnetic-dielectric synergy mechanism are summarized. Simultaneously, the constitutive principle and action principle of the loss types are summarized. For the microwave absorption performances, the properties of BiFeO3- and BaTiO3-based materials in recent years are summarized, including single phase materials, doped materials and composite materials of them. The properties of microwave absorption at room temperature are compared with that at high temperature. Moreover, according to the relation between structure and microstructure of ferroelectric materials and absorption intensity and effective absorption bandwidth of ferroelectric materials, the microwave response mechanisms are summarized. Finally, the problems that hinder the growth of ferroelectric microwave absorption materials are analyzed, and the development outlook of the materials in the future is stated.