Metal Single-Atoms Toward Electromagnetic Wave-Absorbing Materials: Insights and Perspective

Metal single-atoms implanted on nitrogen-doped carbon matrices (M-N_xCs) can effectively adjust local surface electrons and polarization relaxation through coordination structures to significantly enhance the electromagnetic wave (EMW) absorption properties of the materials. However, the precise construction of the geometric and electronic structures of metal single atoms and the discovery of the structure-absorption relationship at the atomic level confront a huge challenge. Herein, this work summarizes the latest progress in metal single-atom engineering of EMW absorbing materials via a comprehensive analysis of M-N_xCs in terms of design principles, modulation strategies, and structure-performance correlations. Subsequently, it highlights the recent progress of several typical M-N_xCs as the EMW absorbing materials, aiming to achieve a complete understanding of the physical effects and atomic-level absorption mechanisms. Finally, current key challenge and future directions of M-N_xCs are presented by focusing on the electromagnetic functional materials. This work provides new insights for the development of atomically dispersed absorbing materials for efficient electromagnetic response functionalities.