Enhanced microwave absorption of multiferroic Co2Z hexaferrite–BaTiO3 composites with tunable impedance matching

Abstract The microwave absorbing properties of multiferroic particulate composites consisting of Co 2 Z hexaferrite and BaTiO 3 (BT) were investigated over a frequency range of 2–18 GHz. The effective complex permeability and permittivity of Co 2 Z–BT composites are shown to be effectively manipulated by varying the weight ratio of the two phases, which consequently demonstrates a strong tunability in the optimal working frequency and minimum reflection loss (RL). For the optimal Co 2 Z–10BT composite, the RL peak at a thickness of 2.0 mm was enhanced by 97.8% in comparison with that of the single phase Co 2 Z hexaferrite. Moreover, the impedance-matched RL characteristics below 10 GHz show a substantial improvement in both thickness and bandwidth with increasing BT content. This work clearly shows the potential to tune the impedance matching and microwave absorption performances of multiferroic composites.