Fe_3O_4/RGO复合材料的制备及其电化学性能研究

以改进Hummers法合成的氧化石墨烯(GO)为前驱体,通过水热法结合烧结工艺制备了四氧化三铁/还原氧化石墨烯(Fe_3O_4/RGO)复合材料。利用X射线衍射(XRD)、拉曼光谱(Raman)、扫描电镜(SEM)、透射电镜(TEM)等手段对复合材料的理化性能进行表征;通过充放电测试、循环伏安(CV)和电化学阻抗谱(EIS)等技术,综合考察了材料的储锂性能及电化学性能增强机制。结果表明,在200和600 m A/g电流密度下,Fe_3O_4/RGO复合负极循环60次后的放电比容量分别保持在709和479 mAh/g,表现出良好的倍率性能;相较于纯Fe_3O_4负极,复合负极呈现出更优异的锂电性能,其电化学性能的改善得益于RGO能增强材料的电导性和结构稳定性。

Synthesis of Fe3O4/RGO composites and their electrochemical performance

With reduced graphene oxide (RGO) as the precursor, Fe₃O₄/RGO composites were synthesized via a hydrothermal method combined with annealing treatment; the crystalline phase, microstructure and component of Fe₃O₄/RGO composites were characterized by XRD, SEM, TEM and Raman spectra. As a new type of lithium battery electrode materials, their electrochemical performance and the corresponding performance enhanced mechanism were investigated by the CV and EIS tests. The results indicate that high loading Fe₃O₄/RGO anodes after charge-discharge 60 cycles show high reversible capacities of 709 mAh/g at 200 mA/g and 479 mAh/g at 600 mA/g, with a very good rate performance. Compared with the Fe₃O₄ electrodes, Fe₃O₄/RGO electrodes exhibit better electrochemical performance, which is associated with a synergy between the stable RGO matrix and its good conductivity; such a nano-sized configuration may not only facilitate the electron conduction but also help to maintain the structural integrity of active materials.