a composite material composed of nanoparticles of transition metal and magnetic ferric oxide , a method of preparing the same , and uses of the same are provided . the composite material is substantially composed of nanoparticles of transition metal or alloy thereof and nanoparticles of magnetic ferric oxide , the size of nanoparticles of transition metal or alloy thereof is in the range of 0 . 7 to 5 nm , the size of nanoparticles of magnetic ferric oxide is in the range of 5 to 50 nm , and the amount of transition metal or alloy thereof is in the range of 0 . 1 to 30 wt %, based on the total weight of composite material , the magnetic ferric oxide is gamma - fe 2 o 3 , fe 3 o 4 , complex obtained from gamma - fe 2 o 3 by partial reduction , or complex obtained from fe 3 o 4 by partial reduction . the composite material has a high reactivity and an extreme selectivity for industrial reaction of hydrogenating halogeno - nitro - aromaticics to obtain halogeno - arylamine , and has important industrial applicability because the problem such as hydrogenolysis - dehalogenation during preparing halogeno arylamine by hydrogenating halogeno - nitro - aromatics is fully resolved by using the composite materials .