The effect of Zn-dopant on the anisotropy constant and reflection loss of the Ba0.6Sr0.4Fe10-xZnxMnTiO19 (x = 0.1, 0.3, and 0.5)

Abstract

In the case of absorption of microwave energy, the overall interaction is represented by impedance matching between the material and the microwave (Zin = Zo) through the resonant frequency mechanism. While the resonant frequency is influenced by the anisotropy field of the material. This research investigated the effect of Zn-dopant on the anisotropy constant and reflection loss of the Ba0.6Sr0.4Fe10-xZnxMnTiO19 (x = 0.1, 0.3, and 0.5). Hexaferrite samples Ba0.6Sr0.4Fe10-xZnxMnTiO19 with × = 0.1, 0.3, and 0.5 have been successfully prepared using high energy milling and by sintering at 1000 °C. Characterization using XRD resulted that all samples being in phase with the hexagonal crystalline structure (P63/mmc). The average crystal size of the three samples is about 44 nm. The shape and size of the surface particles obtained from characterization using scanning electron microscopy are still heterogeneous with particle sizes ranging from 150 to 300 nm. The vibrating sample magnetometer used for magnetization characterization shows that increasing the value of × increases the magnetic saturation value, hence decreasing the anisotropic magnetic field. A vector network analyzer is used to characterize the ability to absorb microwaves, which reveals that the greater the × value, the better the absorbing microwaves. With a bandwidth of 3.6 GHz, the maximum value of reflection loss (RL) recorded for × = 0.5 is – 34.7 dB. It was concluded that the addition of Zn2+ dopant ions into the hexaferrite structure of Ba0.6Sr0.4Fe10-xZnxMnTiO19 can reduce the anisotropy field and increase the reflection loss value, so it is hoped that this composition can be a potential candidate as a microwave absorbent material.