Topological Insulator Materials for High-Performance Microwave Absorption: A Comprehensive Review on Mechanisms and Design Strategies.

Microwave absorption materials (MAMs) hold potential in addressing electromagnetic pollution, advancing microwave communication, and enhancing national defense technologies. However, traditional MAMs suffer from issues such as excessive thickness, difficulty in achieving impedance matching, poor environmental adaptability, and limited functionality, which severely limit their development and application. In recent years, researchers have developed various new absorbers, coupling with metastructure designs and multilayered concentration gradients, significantly enhancing impedance matching and broadening the effective absorption bandwidth (EAB). Among them, topological insulators (TIs) attract significant attention as promising absorbers, due to their topologically protected surface states. They exhibit tunable electrical transport properties and ZT values near room temperature, which present distinct advantages for the development of multifunctional materials combining microwave absorption and thermoelectric functions. This review briefly introduces the basic principles of microwave absorption and elaborates on how topological insulator microwave-absorbing materials (TIMAMs) overcome the limitations of traditional MAMs, as well as their core advantages. Additionally, the recent research progress in TIMAMs is systematically reviewed, highlighting the design strategies for optimizing their performance. Furthermore, the remaining challenges and promising future directions for TIMAMs are identified. This review is expected to provide theoretical guidance on the design strategies for new high-performance and multifunctional absorbers.