The invention discloses a double-shell-structure
carbonyl iron powder composite wave-absorbing material and a preparation method thereof, wherein the composite wave-absorbing material is of a double shell layer core-shell structure, the core is
carbonyl iron powder, the inner layer of the double-shell layer is an insulating layer, and the outer layer of the double-shell layer is a
magnetic layer;the thickness of the insulating layer is 1 nm-1 [mu] m; and the thickness of the
magnetic layer is 1nm-5 [mu] m; the preparation method comprises the following steps:
coating the surface of the
carbonyl iron powder with the insulating layer and
coating the surface of a core-shell structure precursor by a chemical
coprecipitation method. The surface of the carbonyl
iron powder is coated with the double-shell layer by the chemical
coprecipitation method. The
impedance matching characteristic of the material is greatly improved, meanwhile, a large amount of nano-interface
heterojunction is formedat the interfaces of the inner core and the double-shell layer, so that interface polarization is effectively induced, the
scattering effect is formed for
electron migration, and electromagnetic waveloss mechanisms such as multi-reflection absorption, strong ]
ferromagnetic resonance and
eddy current loss and the like of the material are greatly improved, so that the wave absorbing performance of the material is remarkably improved; the composite wave-absorbing material is simple in preparation method, is uniform and compact in
coating and controllable in coating
layer thickness and particlesize.