Superior enhancement in microwave absorption performance of NiFe nanowires inlaid with ZnS Nanocrystals: Synergistic effect of exchange resonance and dielectric polarization relaxation

Lightweight radar absorbing materials (RAMs) play a crucial role in various applications requiring the absorption of electromagnetic radiation. Both large reflection loss and wide effective absorption bandwidth are key issues for RAMs. In the present study, facile and mass producible NiFe nanowires were prepared and inlaid with ZnS nanocrystals (5, 10, and 15 wt%) to improve their microwave absorption properties. The physical materials characteristics of the so-obtained ZnS/NiFe nanowires were examined using X-ray diffraction, scanning and transmission electron microscopy, and electron spectroscopy for chemical analysis, etc. Microwave absorber composites were prepared using 5 wt% optimal ZnS/NiFe nanowires and investigated to reveal their corresponding microwave absorption performance. The experimental results showed that (ZnS) 10 /(Ni 1 Fe 99 ) 90 (i.e., Ni 1 Fe 99 NWs inlaid with 10 wt% ZnS nanocrystals) exhibited significant improvements in both microwave absorption characteristics (complex permeability and permittivity) and performance (reflection loss and effective absorption bandwidth, EAB). The minimum reflection loss was −50.32 dB at 17.60 GHz for a thickness of 1.5 mm, whereas EAB reached 7.59 GHz, ranging from 10.41 to 18.00 GHz for a 1.7 mm thickness. The superior enhancement in microwave absorption performance can be attributed to the synergistic effect of exchange resonance and dielectric polarization relaxation loss induced by the inlay of ZnS nanocrystals on Ni 1 Fe 99 NWs. • (ZnS) 10 /(Ni 1 Fe 99 ) 90 , NiFe nanowires inlaid with ∼5 nm ZnS nanocrystals, were prepared with the addition of 10 % ZnS. • ZnS nanocrystals induced synergistic exchange resonance and dielectric polarization relaxation loss effects on NiFe NWs. • (ZnS) 10 /(Ni 1 Fe 99 ) 90 exhibited excellent improvements in both microwave absorption characteristics and performance.