Electromagnetic wave absorption properties of Ba(CoTi)_xFe_12-2xO₁₉@BiFeO₃ in hundreds of megahertz band

The high-performance electromagnetic (EM) wave absorption material Ba(CoTi)_xFe_12-2xO_19@BiFeO_3 was prepared by solid-state reaction, and its EM wave absorption properties were deeply studied. The results revealed that Ba(CoTi)_xFe_12-2xO_19@BiFeO_3 could obtain excellent absorption properties in hundreds of megahertz by adjusting the Co^2+-Ti^4+ content. The best comprehensive property was obtained for x=1.2, where the optimal reflection loss (RL) value reaches -30.42 dB at about 600 MHz with thickness of 3.5 mm, and the corresponding effective absorption band covers the frequency range of 437 MHz-1 GHz. Moreover, the EM wave absorption mechanism was studied based on the simulation methods. The simulated results showed that the excellent EM wave absorption properties of Ba(CoTi)_xFe_12-2xO_19@BiFeO_3 mainly originated from the internal loss caused by natural resonance, and the interface cancelation further improved the absorption properties and resulted in RL peaks.