摘要
The rational design of composition and microstructure is a proven strategy for developing multifunctional high-performance electromagnetic wave(EMW)absorbers.In this study,a sandwich-structured multilayer nanoplate-like Bi_(2)Fe_(4)O_(9)@Polypyrrole(BFO@PPy)heterostructure was successfully designed and fabricated using an efficient microwave hydrothermal method and an in situ polymerization process.Specifically,Bi_(2)Fe_(4)O_(9)enhances the chemical activity of ammonium persulfate,which in turn initiates the polymerization of pyrrole monomers,resulting in the formation of BFO@PPy heterostructures.The thickness of the PPy coating layer in the BFO@PPy composite can be precisely controlled at the nanoscale,optimizing electromagnetic parameters,conduction losses and interface polarization loss.The fabricated BFO@PPy composite achieves a minimum reflection loss(RL_(min))of-57.8 dB at a thickness of 2.5 mm and an effective absorption bandwidth(EAB)of 6.96 GHz.Furthermore,the EMW absorption performance and mechanism were systematically validated through theoretical calculations,radar cross-sectional simulations(RCS),and first-principles analysis.Notably,the RCS simulation of a 1:1 scale F-22 Raptor fighter model provides a realistic evaluation of the composite's EMW absorption potential in military applications.The efficient fabrication method and superior electromagnetic absorption performance make BFO@PPy a promising candidate for use in complex electromagnetic environments and military domains.Additionally,the BFO@PPy composite exhibits rapid electrothermal conversion at a low voltage(3V),achieving active infrared camouflage within a controllable temperature range,further highlighting its multifunctional properties.
基金
financially supported by the Natural Science Foundation of China(NSFC,No.22165032)
Beijing Natural Science Foundation(No.2242032)
