Ceramic-based electromagnetic wave absorbing materials and concepts towards lightweight, flexibility and thermal resistance

Electromagnetic wave (EMW) absorbing materials have attracted much attention in recent years due to the dramatical increase of high-frequency electronic components and devices, which generate electromagnetic (EM) pollution and cause serious electromagnetic interference (EMI). Ceramics and associated (nano)composites are widely investigated as EMW absorbing materials because of their excellent mechanical properties, chemical/thermal stabilities, and oxidation/corrosion resistance. In addition to outstanding EMW absorbing performance, lightweight, flexibility and thermal resistance at high temperatures strongly affect their practical applications. Therefore, this review highlights the recent progress of advanced ceramic-based EMW absorbing materials by evaluating their vital EMW absorption parameters. First, the fundamentals of EMW absorption are briefly summarized, followed by the effects of phase/chemical composition, micro/nano structure, and morphology on the EMW absorbing performance and associated mechanisms. Furthermore, modern strategies for the preparation of lightweight, flexible and thermal resistant EMW absorbing materials are comprehensively reviewed. Finally, the perspectives of advanced-ceramics as EMW absorbing materials are discussed as well.