The invention belongs to the technical field of preparation and application of nano
composite material, and in particular relates to a method for preparing a magnetic nano metallic iron particle / carbon
nano tube functional composite material. The invention discloses a method for filling a carbon
nano tube with magnetic nano metallic iron particles. The method comprises the following steps: carrying out refluxing treatment on the carbon
nano tube in concentrated
nitric acid, introducing functional groups such as carbonyl, hydroxyl, carboxyl and the like on the surface of the carbon nano tube, carrying out
ultrasonic dispersion and electromagnetic mixing on the treated carbon nano tube in
aqueous solution of bivalent
ferric salt, filling the bivalent
ferric salt in the carbon nano tube through
capillary action, thermally treating the carbon nano tube at
inert atmosphere, decomposing the bivalent
ferric salt filled inside the carbon nano tube into ferric
oxide, and reducing the ferric
oxide into the magnetic nano metallic iron particles by
hydrogen to obtain the
composite material for filling the magnetic nano metallic iron particles into the carbon nano tube, wherein the magnetic nano metallic iron particles can be filled in the carbon nano tubes the calibers of which are 10 to 100 nanometers and which have different structures, and the carbon nano tubes with different calibers as templates can accurately control the size of the magnetic nano metallic iron particles. The method has the advantages of simple process and good
controllability, can make the magnetic nano metallic iron particles evenly filled in the carbon nano tube with high
filling rate, and is convenient for industrialized production; and the prepared nano
magnetic composite material has good application prospect in the fields of high-density magnetic recording materials, wave-absorbing materials,
electromagnetic shielding materials,
nuclear magnetic resonance imaging materials.