利用天然磁铁矿简易绿色合成磁性Fe \begin{document}$ _\bf{3} $\end{document} C \begin{document}$ @ $\end{document} C纳米材料

One simple and environmental friendly synthesis strategy for preparing low-cost magnetic Fe \begin{document}$ _3 $\end{document} C@C materials has been facilely developed using a modified sol-gel approach, wherein natural magnetite acted as the iron source. A chelating polycarboxylic acid such as citric acid (CA) was employed as the carbon source, and it dissolved Fe very effectively, Fe \begin{document}$ _3 $\end{document} O \begin{document}$ _4 $\end{document} and natural magnetite to composite an iron-citrate complex with the assistance of ammonium hydroxide. The core-shell structure of the as-prepared nanocomposites was formed directly by high-temperature pyrolysis. The Fe \begin{document}$ _3 $\end{document} C@C materials exhibited superparamagnetic properties (38.09 emu/mg), suggesting potential applications in biomedicine, environment, absorption, catalysis, etc.