Preparation and Microwave Absorbing Properties of Carbon ...Preparation and Microwave Absorbing Properties of Carbon-Encapsulated Iron Carbide Magnetic Nanoparticles Qing-huai Li 1,
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Preparation and Microwave Absorbing Properties of Carbon-Encapsulated Iron Carbide Magnetic
Nanoparticles
Qing-huai Li1, Xiao-lai Liu1, Dong-lin Zhao2 1Deparment of Physics and Electronic science, Beijing University of Chemical Technology, Beijing 100029, China;
2 Key Laboratory of carbon fiber and functional polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing
Abstract: Carbon-encapsulated iron carbide nanoparticles have been successfully synthesized with pheo-lic-formaldehyde (PF) resin as carbon source, ferric nitrate (FN) as metal precursors and hexamethylenete-tramine as curing agent by a modified carbonization method. The production was conducted in a high-temperature electric furnace. The reaction condition used are as follows: curing temperature 150 ℃, carbonization temperature 700 ℃, with a rate of 1.5 ℃/min, reaction time 1h, nitrogen 20-40 ml/min. The microwave absorbing properties of the carbon-encapsulated iron carbide magnetic nanoparti-cles at the fre-quency range of 2-18 GHz were investigated. The electric resistivity of the sample was high at the microwave frequencies. The occurrence of the natural resonance and the increased magnetic loss in the high-frequency band are significant for impedance matching and electromagnetic wave absorbing. It indicates that the car-bon-encapsulated Fe3C nanoparticles have a potential application in the production of radar absorbing mate-rials.
Keywords: carbon-encapsulated; iron carbide; carbonization; radar absorbing materials
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The 7th National Conference on Functional Materials and Applications