Radoń Adrian, Hawełek Łukasz, Łukowiec Dariusz, Kubacki Jerzy, Włodarczyk Patryk
Łukasiewicz Research Network - Institute of Non-Ferrous Metals, Sowinskiego 5 St., 44-100, Gliwice, Poland.
Faculty of Mechanical Engineering, Silesian University of Technology, Konarskiego 18A St., 44-100, Gliwice, Poland.
Sci Rep. 2019 Dec 27;9(1):20078. doi: 10.1038/s41598-019-56586-6.
The new (Zn,Mg,Ni,Fe,Cd)FeO high entropy ferrite with average crystallite size 11.8 nm was synthesized in two stages by annealing of co-precipitated amorphous precursor. The dielectric spectroscopy confirms, that the electrical conductivity and polarization processes are associated with the mobility of electrons in the structure of ferrite. It was concluded, that the both, high frequency complex dielectric permittivity as well as complex magnetic permeability are strongly temperature and frequency dependent. The AC electrical conductivity is associated with quantum mechanical tunneling of electrons and related to the transfer of charge carriers between Fe and Fe ions. Moreover, the microwave absorption properties were determined. The best microwave absorption properties have been confirmed in the frequency range 1.9 to 2.1 GHz for a layer which is 0.8-1 cm thick. For this range, reflection loss (RL) is lower than -25 dB and shielding effectiveness (SE) lower than -50 dB.
通过对共沉淀非晶前驱体进行退火，分两个阶段合成了平均晶粒尺寸为11.8nm的新型(Zn,Mg,Ni,Fe,Cd)FeO高熵铁氧体。介电谱证实，电导率和极化过程与铁氧体结构中电子的迁移率有关。得出的结论是，高频复介电常数和复磁导率都强烈依赖于温度和频率。交流电导率与电子的量子力学隧穿有关，并且与Fe和Fe离子之间的载流子转移有关。此外，还测定了微波吸收性能。对于厚度为0.8 - 1cm的层，在1.9至2.1GHz的频率范围内证实了最佳的微波吸收性能。在此范围内，反射损耗(RL)低于-25dB，屏蔽效能(SE)低于-50dB。
