Finding easy-to-operate strategy to obtain anode material with well-designed structure and excellent electrochemical performance is necessary to promote the development of the future potassium-ion batteries (PIBs). In this work, we synthesized reduced graphene oxide doping flower-like Fe₇S₈ nanosheets electrode materials using one-step hydrothermal strategy. The rGO@Fe₇S₈ composite is composed of homogeneous Fe₇S₈ and reduced graphene oxide thin nanosheets. This unique structure not only promotes the penetration of electrolyte and increases the conductive of the pure Fe₇S₈ electrode materials, but also relieves the volume expansion of K⁺ during charge/discharge process. When applied this interesting anode electrode for PIBs, the rGO@Fe₇S₈ exhibits excellent electrochemical performance. It delivers a high reversible specific capacity of 445 mAh g⁻¹ at 50 mA g⁻¹, excellent rate performance (284 mAh g⁻¹ at 500 mA g⁻¹ and 237 mAh g⁻¹ at 1000 mA g⁻¹), and a high cycling stability at 100 mA g⁻¹ (maintained 355 mAh g⁻¹ after 300 cycles).

寻找易于操作的策略以获得具有精心设计的结构和优异的电化学性能的负极材料，对于促进未来的钾离子电池（PIB）的发展是必要的。在这项工作中，我们使用一步水热法合成了还原型氧化石墨烯掺杂花状Fe ₇ S ₈纳米片电极材料。rGO @ Fe ₇ S ₈复合材料由均匀的Fe ₇ S ₈和还原的氧化石墨烯薄纳米片组成。这种独特的结构不仅可以促进电解质的渗透，还可以提高纯Fe ₇ S ₈的导电性电极材料，还可以减轻充放电过程中K ⁺的体积膨胀。当将这种有趣的阳极电极用于PIB时，rGO @ Fe ₇ S ₈表现出出色的电化学性能。它提供的445毫安g的高可逆比容量^-1在50mA克^-1，优异的倍率性能（284毫安克^-1以500mA克^-1和237毫安克^-1以1000mA克^-1），和在100 mA g ^-1下具有高循环稳定性（300个循环后保持355 mAh g ^-1）。