Modulation of metal compound structures and optimization of microwave absorption from macro-to atomic scale: A review

Metal compounds, owing to their tunable dielectric properties, excellent structural stability, and diverse coordination environments, exhibit significant potential in the development of high-performance electromagnetic wave absorbers to address electromagnetic pollution in both military and civilian applications. Although previous reviews have reported the research progress of metal compounds in the field of electromagnetic wave absorption, they have two main limitations. Firstly, the previous reviews have rarely summarized the correlation between microwave absorption and structure of metal compounds from the macro-to atomic scale. Secondly, there is a lack of systematic classification and mechanistic interpretation of key regulation strategies. The current review systematically summarizes optimization strategies for the structure of metal compounds and microwave absorption from the macro-to atomic scale. We summary five core approaches: heterogeneous interface, phase engineering, defect engineering, interlayer engineering, and metal single atoms. Through a detailed analysis of the electromagnetic loss mechanisms of these regulation methods, the influence of different structural parameters on complex permittivity, impedance matching, and other critical properties is elucidated. Finally, the current challenges and future development directions of metal compounds in the field of electromagnetic wave absorption are discussed, and valuable insights for future research endeavors are also provided.