Controlled synthesis and shape-dependent electromagnetic wave absorption characteristics of porous Fe3O4 sub-micro particles

Abstract

Porous Fe 3 O 4 sub-micro particles with sphere-like, cube-like and walnut-like morphologies were obtained by a two-step process, and the electromagnetic properties of the Fe 3 O 4 particle/wax composites were investigated. The reflect loss was less than 20 dB for all of the composites in different frequency ranges. The cube-like and walnut-like Fe 3 O 4 composites exhibit improved complex permittivity and permeability and dual-frequency and wide bandwidth absorption characteristics, which is mainly attributed to the larger shape anisotropy. Such a high absorption property indicates that these porous Fe 3 O 4 particles with various morphologies are very promising for electromagnetic wave absorptive materials. magnetic materials, electromagnetic absorption, magnetic properties, crystal structure PACS number(s): 77.22.Gm, 73.63.Bd, 71.20.Nr Citation: Chen Y J, Zhang Y, Xiao G, et al. Controlled synthesis and shape-dependent electromagnetic wave absorption characteristics of porous Fe 3 O 4 sub-micro particles.

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