Iron disulfide is considered to be a potential anode material for sodium-ion batteries due to its high theoretical capacity. However, its applications are seriously limited by the weak conductivity and large volume change, which results in low reversible capacity and poor cycling stability. Herein, reduced graphene oxide-wrapped FeS₂ (FeS₂/rGO) composite was fabricated to achieve excellent electrochemical performance via a facile two-step method. The introduction of rGO effectively improved the conductivity, BET surface area, and structural stability of the FeS₂ active material, thus endowing it with high specific capacity, good rate capability, as well as excellent cycling stability. Electrochemical measurements show that the FeS₂/rGO composite had a high initial discharge capacity of 1263.2 mAh g⁻¹ at 100 mA g⁻¹ and a high discharge capacity of 344 mAh g⁻¹ at 10 A g⁻¹, demonstrating superior rate performance. After 100 cycles at 100 mA g⁻¹, the discharge capacity remained at 609.5 mAh g⁻¹, indicating the excellent cycling stability of the FeS₂/rGO electrode.

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由于其高的理论容量，二硫化铁被认为是钠离子电池的潜在阳极材料。但是，其应用受到电导率低和体积变化大的严重限制，这导致可逆容量低和循环稳定性差。在此，通过简便的两步法制备了还原的氧化石墨烯包裹的FeS ₂（FeS ₂ / rGO）复合材料，以实现优异的电化学性能。引入rGO可有效改善FeS ₂活性材料的电导率，BET表面积和结构稳定性，从而赋予其高比容量，良好的倍率性能以及出色的循环稳定性。电化学测量表明，FeS ₂/ rGO复合材料在100 mA g ^-1时具有1263.2 mAh g ^-1的高初始放电容量，在10 A g ^-1时具有344 mAh g ^-1的高放电容量，证明了优异的倍率性能。在100mA g ^-1下100次循环后，放电容量保持在609.5mAh g ^-1，表明FeS ₂ / rGO电极的优异的循环稳定性。

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