Characterization and synthesis of Fe3O4@C nanoparticles by in-situ solid-phase method

Abstract Fe 3 O 4 @C nanoparticles were successfully synthesized by an in situ solid-phase method using FeSO 4 , FeS 2 , and PVP K30 as the starting materials under the nitrogen atmosphere. In addition, the mechanism of the synthetic of Fe 3 O 4 @C nanoparticles was studied through in situ characterizations. The results showed that the pyrolysis of PVP K30 participated in the solid-phase reaction and resulted in the formation of carbon shells and a reduction in particle size. The structure of the Fe 3 O 4 @C nanoparticles was core–shell with the average particle size of ∼30 nm and the thickness of the carbon shell of ∼2 nm. Besides, the Raman spectrum revealed that the carbon shell mostly existed in the form of amorphous carbon. The surface area and the pore volume of the Fe 3 O 4 @C nanoparticles were estimated to be 37.74 m 2 g −1 and 0.227 cm 3 g −1 . Magnetization hysteresis curve exhibited the values of coercivity and remanence and saturation magnetization are found to be approximately 0.16 kOe, 12.8 emu g −1 , and 77 emu g −1 , respectively.