Microwave absorption properties of carbon black and tetrapod-like ZnO whiskers composites

CB/T-ZnO/EP composites were prepared using carbon black (CB) and tetrapod-like ZnO whiskers (T-ZnO) as absorbents and epoxy resin (EP) as binder. The electromagnetic parameters and microwave absorption properties of the composites were measured in the frequency range of 2-18 GHz. The influences of absorbents concentration and composites thickness on microwave absorption properties were studied. Results show that the minimum reflection loss for CB/T-ZnO/EP composites is −19.31 dB at 10.4 GHz and the bandwidth corresponding to reflection loss blow −5 dB is 9.68 GHz, when the content of CB and T-ZnO whiskers are 7 wt% and 13 wt%, respectively, and the composites thickness is 3 mm. The mechanisms of microwave absorption performance for CB/T-ZnO/EP composites were briefly discussed. It is supposed that CB/T-ZnO/EP composites have the potential to be applied as microwave absorber with high microwave-absorption and light weight.