A novel biomass-derived carbon@ZnO@ZnSe composites for efficient electromagnetic wave absorption

A novel biomass carbon-based ternary composite coated with ZnO and ZnSe was synthesized by activated carbonization and hydrothermal method. The composition, microstructure and electromagnetic wave (EMW) absorption performance and related mechanism of the composites were investigated in detail. The unique coating structure of lamellar ZnO and spherical ZnSe facilitates multiple reflection and scattering of EMWs, thereby enhancing the dissipation of EMW energy. Moreover, the incorporation of highly conductive ZnO and ZnSe not only enhances the polarization loss and conductivity loss of CBP@ZnO@ZnSe composites, but also improves the impedance matching, further optimizing the EMW absorption property greatly. The CBP@ZnO@ZnSe composites exhibited enhanced EMW absorption performance, characterized by a minimum reflection loss of -24.57 dB and an effective absorption bandwidth of 3.43 GHz at 2.89 mm, owing to the synergistic interplay of favorable impedance matching and attenuation ability. In addition, radar cross section simulation results further demonstrated that CBP@ZnO@ZnSe composites have good electromagnetic energy dissipation effect in practical applications. This study not only offers a simple and feasible method for preparing CBP@ZnO@ZnSe composites with excellent EMW absorption properties, but also serves as a reference for the research of ternary composites based on bio-derived carbon.