In this work, we developed a simple one-step hydrothermal method to successfully prepare Fe3O4/FeS-reduced graphene oxide (Fe3O4/FeS/rGO) composite directly, which is a novel Lithium-ion batteries (LIBs) anode material. The characterization of Fe3O4/FeS/rGO composite demonstrates that octahedral Fe3O4/FeS particles are uniformly deposited on the rGO, leading to a strong synergy between them. The excellent structural design can make Fe3O4/FeS/rGO composite to have higher reversible capacity (744.7[Formula: see text]mAh/g at 0.1[Formula: see text]C after 50 cycles), excellent cycling performance and superior rate capability. This outstanding electrochemical behavior can be attributed to the conductivity network of rGO, which improves the composite electrode conductivity, facilitates the diffusion and transfer of ions and prevents the aggregation and pulverization of Fe3O4/FeS particles during the charging and discharging processes. Moreover, the Fe3O4/FeS/rGO electrode surface is covered with a thin solid-electrolyte interface (SEI) film and the octahedral structure of Fe3O4/FeS particles is still clearly visible, which indicates that composite electrode has excellent interface stability. We believe that the design of this composite structure will provide a new perspective for the further study of other transition metal oxides for LIBs.

中文翻译：

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锂离子电池用Fe3O4/FeS/rGO复合材料结构优良的高性能负极材料

在这项工作中，我们开发了一种简单的一步水热法成功制备 Fe3○4/FeS-还原氧化石墨烯（Fe3○4/FeS/rGO) 直接复合，是一种新型的锂离子电池（LIBs）负极材料。Fe的表征3○4/FeS/rGO 复合材料表明八面体 Fe3○4/FeS 颗粒均匀地沉积在 rGO 上，导致它们之间的强大协同作用。优良的结构设计可以使铁3○4/FeS/rGO复合材料具有更高的可逆容量（50次循环后在0.1[公式：见文本]C时为744.7[公式：见文本]mAh/g），优异的循环性能和优异的倍率能力。这种优异的电化学行为可以归因于rGO的电导网络，它提高了复合电极的电导率，促进了离子的扩散和转移，防止了Fe的聚集和粉碎3○4/FeS颗粒在充电和放电过程中。此外，铁3○4/FeS/rGO电极表面覆盖有薄的固体电解质界面（SEI）膜和Fe的八面体结构3○4/FeS颗粒依然清晰可见，说明复合电极具有优异的界面稳定性。我们相信，这种复合结构的设计将为进一步研究用于锂离子电池的其他过渡金属氧化物提供新的视角。