Magnetic and microwave-absorption properties of SnO-coated α-Fe(Sn) nanocapsules

A series of SnO-coated α-Fe solid-solution nanocapsules were fabricated by a modified arc-discharge technique from Fe1−x Sn x targets with x = 0, 2, 3, 4 and 5 at%. The core and shells change with changing Sn concentration (0, 2, 3, 4 and 5 at%) in the Fe1−x Sn x targets used in the preparation. An in-depth study of the complex permittivity and permeability reveals that the SnO-coated α-Fe solid-solution nanocapsules with 3 at% Sn exhibit excellent microwave-absorption properties among the present SnO-coated Fe solid-solution nanocapsules, due to a proper electromagnetic match in the microstructure, the strong natural resonance as well as dipolar polarization mechanisms.