Abstract Microsized cobalt sulfide is prepared via a solvothermal method in ethylenediamine solution by using CoCl2·6H2O as cobalt resource and thioacetamide as the sulfiding reagent. By varying the reaction parameters, CoS-24 and CoS-48 are obtained at 180 °C for 24 h and 48 h, respectively. Scanning electron microscopy and transmission electron microscopy images reveal that the microstructures are both assembled by nanosheets with width in the range of 130–160 nm and thickness of 30–50 nm. When used in SIBs, the more dispersed CoS-48 electrode exhibits superior sodium storage performances than that of CoS-24. For CoS-48, a specific capacity of 753 mAh g−1 is delivered at the current density of 100 mA g−1 in the potential window of 0.1–3.0 V. Moreover, 392 mAh g−1 can still be maintained at the current density of 1000 mA g−1 after 200 cycles, corresponding to 80% retention. These results demonstrate the potential of the carbon-free cobalt sulfide as high performance anode materials for energy storage.

中文翻译：

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乙二胺辅助合成微型硫化钴作为钠离子电池的先进负极材料

摘要 以CoCl2·6H2O为钴源，硫代乙酰胺为硫化剂，在乙二胺溶液中采用溶剂热法制备了微尺寸硫化钴。通过改变反应参数，CoS-24 和 CoS-48 在 180 °C 下分别获得 24 小时和 48 小时。扫描电子显微镜和透射电子显微镜图像显示，微结构均由宽度在 130-160 nm 范围内、厚度在 30-50 nm 范围内的纳米片组装而成。当用于 SIB 时，更分散的 CoS-48 电极表现出比 CoS-24 更好的钠存储性能。对于 CoS-48，在 100 mA g-1 的电流密度下，在 0.1-3.0 V 的电位窗口中，提供了 753 mAh g-1 的比容量。此外，在电流下仍可保持 392 mAh g-1 200 次循环后密度为 1000 mA g-1，相当于 80% 的保留率。这些结果证明了无碳硫化钴作为高性能储能负极材料的潜力。