posted on 2020-03-11, 21:29authored byNa Gao, Wen-Ping Li, Wen-Shou Wang, Da-Peng Liu, Yi-Min Cui, Lin Guo, Guang-Sheng Wang
Lightweight, broad-band, and highly efficient microwave-absorbing
materials (MAMs) with tunable electromagnetic properties are in high
demand. However, the absorption properties are limited by the simple
loss mechanism in commonly used absorbing materials. Here, we tested
the microwave-absorbing properties of Fe–NiS2/NiS/poly(vinylidene
fluoride) (PVDF) in the frequency range of 2–18 GHz. For the
2.5% Fe–NiS2/NiS/PVDF with the filling content of
20 wt %, the maximum reflection loss can reach −61.72 dB at
14.88 GHz, and the bandwidth can reach 3.8 GHz with the reflection
loss value below −10 dB. Loss mechanisms of different composites
were analyzed on the basis of their magnetic and dielectric properties
using both experimental and computational methods. The results indicate
that strong microwave absorption property is achieved through a balancing
of dielectric loss and magnetic loss. These findings present a new
strategy for the future design of MAMs.