中国物理B ›› 2013, Vol. 22 ›› Issue (5): 58101-058101.doi: 10.1088/1674-1056/22/5/058101

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Enhancement of microwave absorption of nanocomposite BaFe12O19/α-Fe microfibers

杨新春a, 刘瑞江b, 沈湘黔a, 宋福展a, 景茂祥a, 孟献丰a   

  1. a Institute of Advanced Materials, Jiangsu University, Zhenjiang 212013, China;
    b School of Pharmacy, Jiangsu University, Zhenjiang 212013, China
  • 收稿日期:2012-08-26 修回日期:2012-10-10 出版日期:2013-04-01 发布日期:2013-04-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 51274106 and 51202091), the Natural Science Foundation of Higher Education of Jiangsu Province, China (Grant No. 12KJA430001), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20103227110006), the Science and Technology Support Program of Jiangsu Province, China (Grant No. BE2012143), and the Postgraduate Cultivation and Innovation Project of Jiangsu Province, China (Grant No. CXZZ11_0557).

Enhancement of microwave absorption of nanocomposite BaFe12O19/α-Fe microfibers

Yang Xin-Chun (杨新春)a, Liu Rui-Jiang (刘瑞江)b, Shen Xiang-Qian (沈湘黔)a, Song Fu-Zhan (宋福展)a, Jing Mao-Xiang (景茂祥)a, Meng Xian-Feng (孟献丰)a   

  1. a Institute of Advanced Materials, Jiangsu University, Zhenjiang 212013, China;
    b School of Pharmacy, Jiangsu University, Zhenjiang 212013, China
  • Received:2012-08-26 Revised:2012-10-10 Online:2013-04-01 Published:2013-04-01
  • Contact: Shen Xiang-Qian E-mail:shenxq@ujs.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 51274106 and 51202091), the Natural Science Foundation of Higher Education of Jiangsu Province, China (Grant No. 12KJA430001), the Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20103227110006), the Science and Technology Support Program of Jiangsu Province, China (Grant No. BE2012143), and the Postgraduate Cultivation and Innovation Project of Jiangsu Province, China (Grant No. CXZZ11_0557).

摘要: Nanocomposite BaFe12O19/α-Fe microfibers with diameters of about 1-5 μm are prepared by the organic gel-thermal selective reduction process. The binary phase of BaFe12O19 and α-Fe is formed after reduction of the precursor BaFe12O19/α-Fe2O3microfibers at 350 ℃ for 1 h. These nanocomposite microfibers are fabricated from α-Fe (16-22 nm in diameter) and BaFe12O19 particles (36-42 nm in diameter) and basically exhibit a single-phase-like magnetization behaviour, with a high saturation magnetization and coercive force arising from the exchange-coupling interactions of soft α-Fe and hard BaFe12O19. The microwave absorption characteristics in a 2-18 GHz frequency range of the nanocomposite BaFe12O19/α-Fe microfibers are mainly influenced by their mass ratio of α-Fe/BaFe12O19 and specimen thickness. It is found that the nanocomposite BaFe12O19/α-Fe microfibers with a mass ratio of 1:6 and specimen thickness of 2.5 mm show an optimal reflection loss (RL) of -29.7 dB at 13.5 GHz and the bandwidth with RL exceeding -10 dB covers the whole Ku-band (12.4-18.0 GHz). This enhancement of microwave absorption can be attributed to the heterotructure of soft, nano, conducting α-Fe particles embedded in hard, nano, semiconducting barium ferrite, which improves the dipolar polarization, interfacial polarization, exchange-coupling interaction, and anisotropic energy in the nanocomposite BaFe12O19/α-Fe microfibers.

关键词: barium ferrite, nanocomposites, microfibers, microwave absorber

Abstract: Nanocomposite BaFe12O19/α-Fe microfibers with diameters of about 1-5 μm are prepared by the organic gel-thermal selective reduction process. The binary phase of BaFe12O19 and α-Fe is formed after reduction of the precursor BaFe12O19/α-Fe2O3microfibers at 350 ℃ for 1 h. These nanocomposite microfibers are fabricated from α-Fe (16-22 nm in diameter) and BaFe12O19 particles (36-42 nm in diameter) and basically exhibit a single-phase-like magnetization behaviour, with a high saturation magnetization and coercive force arising from the exchange-coupling interactions of soft α-Fe and hard BaFe12O19. The microwave absorption characteristics in a 2-18 GHz frequency range of the nanocomposite BaFe12O19/α-Fe microfibers are mainly influenced by their mass ratio of α-Fe/BaFe12O19 and specimen thickness. It is found that the nanocomposite BaFe12O19/α-Fe microfibers with a mass ratio of 1:6 and specimen thickness of 2.5 mm show an optimal reflection loss (RL) of -29.7 dB at 13.5 GHz and the bandwidth with RL exceeding -10 dB covers the whole Ku-band (12.4-18.0 GHz). This enhancement of microwave absorption can be attributed to the heterotructure of soft, nano, conducting α-Fe particles embedded in hard, nano, semiconducting barium ferrite, which improves the dipolar polarization, interfacial polarization, exchange-coupling interaction, and anisotropic energy in the nanocomposite BaFe12O19/α-Fe microfibers.

Key words: barium ferrite, nanocomposites, microfibers, microwave absorber

中图分类号:  (New materials: theory, design, and fabrication)

  • 81.05.Zx
81.16.-c (Methods of micro- and nanofabrication and processing) 73.40.Sx (Metal-semiconductor-metal structures)