Effect of Thickness on Microwave Absorption Properties of Ba3Co2Fe24O41 Hexaferrite
Main Article Content
Abstract
This study investigates the thickness-dependent microwave absorption performance of Ba3Co2Fe24O41 (Co2Z) hexaferrite synthesized via a conventional solid-state reaction method. Structural analysis and Rietveld refinement confirm the dominance of the Z-type phase over the Y-type phase. SEM observations show plate-like hexagonal particles, with a crystallite size of ~117.5 nm and an average grain size of ~2.56 μm. Magnetic measurements indicate soft magnetic behavior, with a saturation magnetization of 58.80 emu/g and a low coercivity of 91.73 Oe. The as-prepared Co2Z sample exhibits strong microwave absorption performance over a wide frequency range, which can be effectively tuned by adjusting the sample thickness from 1 to 6 mm. The optimal absorption intensity reaches −27.7 dB at 2.75 GHz for a thickness of 6 mm, corresponding to ~99.9% attenuation of incident electromagnetic waves. In addition, a broad effective absorption bandwidth (EAB) of 5.5 GHz is obtained at 2 mm in Ku band, while the maximum EAB of ~6.1 GHz is achieved at an optimal thickness of 2.5 mm, covering multiple frequency bands from C to Ku. The enhanced microwave absorption performance can be attributed to the synergistic effects of impedance matching, natural ferromagnetic resonance, and multiple dielectric relaxation processes. These results indicate that the Co2Z hexaferrite is a promising candidate for tunable microwave absorption applications.
Keywords:
solid-state reaction, Z-type hexaferrite, MAMs, microwave absorption, reflection loss, effective absorption bandwidth
References
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[6] X. Gao, X. Wang, J. Cai, Y. Zhang, J. Zhang, S. Bi, Z.L. Hou, CNT cluster arrays grown on carbon fiber for excellent green EMI shielding and microwave absorbing, Carbon, Vol. 211, 2023, pp. 118083, https://doi.org/10.1016/j.carbon.2023.118083.
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[9] D. Meisak, A. Plyushch, J. Macutkevič, R. Grigalaitis, A. Sokal, K.N. Lapko, A. Selskis, P.P. Kuzhir, J. Banys, Effect of temperature on shielding efficiency of phosphate-bonded CoFe2O4 – xBaTiO3 multiferroic composite ceramics in microwaves, Journal of Materials Research and Technology, Vol. 24, 2023, pp. 1939–1948, https://doi.org/10.1016/j.jmrt.2023.03.124.
[10] D. Guo, W. Kong, J. Feng, X. Li, X. Fan, Synthesis, electromagnetic and microwave absorption properties of Ba3Co2Fe24O41 hexaferrites for GHz application, Materials Science and Engineering: B, Vol. 228, 2018, pp. 213–217, https://doi.org/10.1016/j.mseb.2017.12.008.
[11] C.T.A. Xuan, P.T. Tho, N.D. Xuan, T.A. Ho, P.T.V. Ha, L.T.Q. Trang, N.Q. Tuan, D.H. Manh, T.D. Thanh, N. Tran, Microwave absorption properties for composites of CoFe2O4/carbonaceous-based materials: A comprehensive review, Journal of Alloys and Compounds, Vol. 990, 2024,https://doi.org/10.1016/j.jallcom.2024.174429.
[12] N. Shao, J. Li, S. Che, J. Zheng, L. Qiao, Y. Ying, J. Yu, W. Li, L and S band microwave absorption properties of Z-type hexaferrite Ba3Co2Fe24O41 synthesized at low temperature, Journal of Alloys and Compounds, Vol. 968, 2023, pp. 171926, https://doi.org/10.1016/j.jallcom.2023.171926.
[13] M. Green, X. Chen, Recent progress of nanomaterials for microwave absorption, Journal of Materiomics, Vol. 5, 2019, pp. 503–541, https://doi.org/10.1016/j.jmat.2019.07.003.
[14] T. Tachibana, T. Nakagawa, Y. Takada, K. Izumi, T.A. Yamamoto, T. Shimada, S. Kawano, X-ray and neutron diffraction studies on iron-substituted Z-type hexagonal barium ferrite: Ba3Co2-xFe24+xO41 (x = 0-0.6), Journal of Magnetism and Magnetic Materials, Vol. 262, 2003, pp. 248–257, https://doi.org/10.1016/S0304-8853(02)01498-1.
[15] K. Singha, R. Jasrotia, L. Wy, J. Prakash, A. Verma, P. Kumar, S. Kumar, M. Chandel, V. Pratap, S. Thakur, R. Das, A. Kandwal, H.H. Hegazy, P. Sharma, A review of Z-type hexaferrite based magnetic nanomaterials : Structure , synthesis , properties , and potential applications, Progress in Solid State Chemistry, Vol. 70, 2023, pp. 100404, https://doi.org/10.1016/j.progsolidstchem.2023.100404.
[16] X. Liu, Z. Yang, X. Liao, X. Liu, A. Huang, Effect of divalent metal ions substitution on the magnetic properties of Ba3Co2-xMexFe24O41 (Me = Zn2+, Ni2+) hexagonal ferrites, Journal of Magnetism and Magnetic Materials, Vol. 596, 2024, pp. 171964, https://doi.org/10.1016/j.jmmm.2024.171964.
[17] A. Thakur, A. Manhas, D. Sharma, R. Duglet, M. Singh, Magnetic studies of dysprosium and indium doped Co2Z hexaferrites, Journal of Magnetism and Magnetic Materials, Vol. 566, 2023, pp. 170309, https://doi.org/10.1016/j.jmmm.2022.170309.
[18] X. Huo, Z. Cheng, M. Qu, X. Yang, Y. Jing, X. Jian, H. Su, Modification of magnetic and dielectric properties in Mn3+ substituted Co2Z hexaferrite for miniaturized patch antenna, Journal of Alloys and Compounds, Vol. 1010, 2025, pp. 178174, https://doi.org/10.1016/j.jallcom.2024.178174.
[19] Y. Ma, Y. yong Cao, J. Li, Y. Lei, Y. Xiao, Y. Liu, Z. Zhong, Exchange interactions in Ba3Co2Fe24O41 ferrite, Journal of Magnetism and Magnetic Materials, Vol. 624, 2025, pp. 173046, https://doi.org/10.1016/j.jmmm.2025.173046.
[20] J.T. Lim, C.S. Kim, Hyperfine structure and magnetic properties of Zn doped Co2Z hexaferrite investigated by high-field Mössbauer spectroscopy, Journal of Applied Physics, Vol. 117, 2015, pp. 3–6, https://doi.org/10.1063/1.4918954.
[21] R.C. Pullar, Hexagonal ferrites: A review of the synthesis, properties and applications of hexaferrite ceramics, Progress in Materials Science, Vol. 57, 2012, pp. 1191–1334, https://doi.org/10.1016/j.pmatsci.2012.04.001.
[22] T.D. Thanh, N. Tran, N. Thi Viet Chinh, N. Thi Ngoc Anh, D.H. Manh, N.Q. Tuan, Excellent microwave absorption performances of cobalt-doped SrFe12O19 hexaferrite with varying incident angles, Journal of Alloys and Compounds, Vol. 952, 2023, pp. 170060, https://doi.org/10.1016/j.jallcom.2023.170060.
[23] Y. Gao, Q. Wu, J. Song, Q. Man, Achieving broad absorption bandwidth of Ba2Co2Fe12O22 ferrites by adjusting the sintering temperature, Journal of Magnetism and Magnetic Materials, Vol. 554, 2022, pp. 169312, https://doi.org/10.1016/j.jmmm.2022.169312.
[24] P.T. Tho, N. Tran, C.T.A. Xuan, T.Q. Dat, T.N. Bach, T.A. Ho, N.Q. Tuan, D.T. Khan, N.L. Tuyen, N. V. Khien, Microwave absorption performance of La1.5Sr0.5NiO4/SrFe12O19 composites with thin matching thickness, Ceramics International, Vol. 50, 2024, pp. 46683–46694, https://doi.org/10.1016/j.ceramint.2024.09.020.
[25] N. Tran, T.L. Phan, N.T. Dang, D.S. Yang, B.W. Lee, Crystalline and electronic structure and magnetic properties of La-doped Ba3Co2Fe24O41 hexaferrites, Journal of Physics and Chemistry of Solids, Vol. 131, 2019, pp. 55–61, https://doi.org/10.1016/j.jpcs.2019.03.015.
[26] Y. Lei, X. Wang, X. Huo, K. Liu, Y. Liu, P. Zhang, H. Zhang, J. Li, Enhanced magnetodielectric properties of Co2Z ferrite ceramics for ultrahigh frequency applications achieved via Cr3+ ion doping, Ceramics International, Vol. 49, 2023, pp. 26675–26682, https://doi.org/10.1016/j.ceramint.2023.05.203.
[27] S. Kračunovska, J. Töpfer, Synthesis, sintering behavior and magnetic properties of Cu-substituted Co2Z hexagonal ferrites, Journal of Materials Science: Materials in Electronics, Vol. 22, 2011, pp. 467–473, https://doi.org/10.1007/s10854-010-0161-4.
[28] M.M. Costa, G.F.M.P. Júnior, A.S.B. Sombra, Dielectric and impedance properties' studies of the of lead doped ( PbO ) - Co2Y type hexaferrite ( Ba2Co2Fe12O22 ( Co2Y )), Materials Chemistry and Physics, Vol. 123, 2010, pp. 35–39, https://doi.org/10.1016/j.matchemphys.2010.03.026.
[29] H. Zhang, J. Zhou, Y. Wang, L. Li, Z. Yue, Z. Gui, The effect of Zn ion substitution on electromagnetic properties of low-temperature fired Z-type hexaferrite, Vol. 28, 2002, pp. 917–923.
[30] J. Song, Y. Gao, G. Tan, Q. Man, Z. Wang, Comparative study of microwave absorption properties of Ni–Zn ferrites obtained from different synthesis technologies, Ceramics International, Vol. 48, 2022, pp. 22896–22905, https://doi.org/10.1016/j.ceramint.2022.04.237.
[31] Q.U.A. Shahid, M.A. Khan, S. Gulbadan, G.A. Ashraf, R.T. Rasool, Impact of erbium substitution on structural, dielectric, spectral, and microwave absorption properties of Ba3Co2Fe24O41 Z-type hexa-ferrites for microwave devices applications, Ceramics International, Vol. 49, 2023, pp. 27866–27877, https://doi.org/10.1016/j.ceramint.2023.06.003.
[32] J. Wu, J. Li, B. Lu, Y. Zhang, Y. Chen, K. Sun, D. Chen, Q. Li, Y. Li, I. Devices, E. Science, Tuning magneto-dielectric properties of Co2Z ferrites via Gd doping for high-frequency applications, Chinese Physics B, Vol. 32, 2023, pp. 097501, https://doi.org/DOI: 10.1088/1674-1056/acc3f7.
[33] Y. Yu, M. Wang, Y. Bai, B. Zhang, L. An, J. Zhang, B. Zhong, Tuning the inner hollow structure of lightweight amorphous carbon for enhanced microwave absorption, Chemical Engineering Journal, Vol. 375, 2019, pp. 121914, https://doi.org/10.1016/j.cej.2019.121914.
[34] Z.L. Hou, X. Gao, J. Zhang, G. Wang, A perspective on impedance matching and resonance absorption mechanism for electromagnetic wave absorbing, Carbon, Vol. 222, 2024, pp. 118935, https://doi.org/10.1016/j.carbon.2024.118935.