Dual magnetic particles modified carbon nanosheets in CoFe/Co@NC heterostructure for efficient electromagnetic synergy

Dual magnetic particles-modified carbon materials have great potential in terms of ultrathin thickness (≤ 2 mm) and super electromagnetic wave (EMW) absorption (≤ -70 dB). Herein, using CoFe-metal-organic framework (MOF)-derived CoFe/Co@NC heterostructures composed of hollow CoFe nanospheres, solid Co nanospheres, and nitrogen-doped carbon (NC) nanosheets, we demonstrate how the dual magnetic particles regulate the electromagnetic response behavior of the heterostructure and thus steer the efficient EMW absorption performance. That is, CoFe/Co@NC heterostructure inherits an ultra-strong reflection loss (R L) of -73.8 dB at 1.78 mm. The effective absorption bandwidth (EAB) value is also available up to 5.4 GHz. Moreover, computer simulation technology (CST) simulations reveal the good radar stealth effect of heterostructures. Experimentally, the outstanding EMW absorption of CoFe/Co@NC heterostructure is due to a large number of heterointerfaces, good conductive networks and dual magnetic nanoparticles, which bring considerable interface polarization, conduction loss, and magnetic loss characteristics. These findings underscore the importance of electromagnetic synergy induced by dual magnetic particles for steering the electromagnetic response of EMW absorbers.