Synthesis of Multilayered Fe₃O₄@SnO₂@C Nanocomposites via Amino-Functionalization

Nanocomposites composed of different materials can realize original physicochemical and electrical properties that will be fundamental for future technologies. Magnetite (Fe₃O₄) nanoparticles, with unique magnetic and electrochemical properties, have attracted significant attention in many fields, including recording material, bio, electromagnetic interference shielding, and secondary batteries. In particular, tin dioxide (SnO₂), an n-type semiconductor, has a high synergistic effect with Fe₃O₄, so many researchers have tried to combine these two materials. Nevertheless, composite materials composed of only oxide have low electrical conductivity and poor performance, so the help of high-conductivity materials is sometimes required. In this study, a systematic method for fabricating multilayered Fe₃O₄@SnO₂@C nanocomposites via surface treatment/modification and carbonization was proposed. Silane/polymer-based amino-functionalization has been introduced to coat carbon. Also, the carbon layer was formed on the surface of Fe₃O₄@SnO₂ nanoparticles through the dehydration of the carbon precursor using sulfuric acid at atmospheric pressure. Finally, the synthesized nanocomposite's structure, surface properties, dispersibility, and magnetism were evaluated.