Characterization microwave absorption from active carbon/BaSmxFe12−xO19/polypyrrole composites analyzed with a more rigorous method

  • Ying Liu
  • Michael G. B. Drew
  • Yue LiuEmail author


There are problems with the conventional method of determining reflection loss for microwave absorption material. In particular, it is concluded that the ability of a material to absorb microwaves is related with sample thickness of the material. Based on this wrong conclusion, a model is then proposed on the quarter-wavelength’s sample thickness. However, it is shown in the present work that the conclusion together with the model is incorrect and that the associated experimental work needs therefore to be re-evaluated. In this work we evaluate our own experimental work on microwave absorption of a composite correctly and demonstrate the errors in the previous method. C/BaSmxFe12−xO19 has been prepared by the hydrothermal method and C/BaSmxFe12−xO19/PPY by in situ polymerization. The microwave absorption of the composites has then been characterized with an appropriate method. The maximum reflection loss was achieved at x = 0.2 consistently for both C/BaSmxFe12−xO19 and C/BaSmxFe12−xO19/PPY. The result shows that the components of active carbon, polypyrrole, and ferrite in the composites have a positive cooperating effect on microwave absorption. It is also clearly demonstrated that the result is independent of sample thickness.


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Authors and Affiliations

  1. 1.College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyangPeople’s Republic of China
  2. 2.School of ChemistryThe University of ReadingReadingUK

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