Cubic MnS-FeS2 Composites Derived from a Prussian Blue Analogue as Anode Materials for Sodium-Ion Batteries with Long-Term Cycle Stability
Cubic MnS-FeS2 Composites Derived from a Prussian Blue Analogue as Anode Materials for Sodium-Ion Batteries with Long-Term Cycle Stability
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源自普鲁士蓝类似物的立方 MnS-FeS2 复合材料作为具有长期循环稳定性的钠离子电池负极材料
DOI：
10.1021/acsami.0c10874
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发表时间：
2020
影响因子：
9.5
通讯作者：
Sun Shi-Gang
中科院分区：
文献类型：
--
作者：
Liu Qian;Zhang Shao-Jian;Xiang Cheng-Cheng;Luo Chen-Xu;Zhang Peng-Fang;Shi Chen-Guang;Zhou Yao;Li Jun-Tao;Huang Ling;Sun Shi-Gang
制备了具有中空结构的立方相N，S共掺杂碳包覆MnS-FeS 2复合材料（MnS-FeS 2 @NSC），并将其用作钠离子电池负极材料。MnS-FeS 2 @NSC具有优异的循环性能和高倍率性能，在0.1 A g-1的电流密度下循环800次后，其可逆容量为501.0 mAh g-1，容量保持率为81%。更重要的是，MnS-FeS 2 @NSC阳极具有长期循环稳定性;在4 A g-1下循环14 500次后，容量可保持在134.0 mAh g-1。动力学分析表明，Na+存储遵循赝电容主导过程，这归因于MnS-FeS 2 @NSC材料的优异速率性能的起源。电化学性能的提高主要归因于中空结构和N，S共掺杂的碳包覆结构，它们可以减小钠离子和电子的扩散距离，缓解钠离子插入/拔出过程中的体积膨胀，并有效地保持结构完整性。X射线衍射（XRD）结果表明，在MnS的钠化过程中存在FeS 2钠化和MnS钠化两步过程，电化学阻抗谱（EIS）结果表明，金属元素在预转化反应中的积累促进了进一步转化过程中电子和离子的转移.
Cubic N,S codoped carbon coating MnS–FeS2composites (MnS–FeS2@NSC) with a hollow structure were prepared and used as anode materials for sodium-ion batteries. MnS–FeS2@NSC exhibits excellent cycle performance and high rate capability and delivered a reversible capacity of 501.0 mAh g–1after 800 cycles at a current density of 0.1 A g–1with a capacity retention of 81%. More importantly, the MnS–FeS2@NSC anode holds long-term cycle stability; the capacity can remain 134.0 mAh g–1after 14 500 cycles at 4 A g–1. Kinetic analysis demonstrated that Na+storage follows a pseudocapacitive dominating process, which is ascribed to the origin of the outstanding rate performance of the MnS–FeS2@NSC material. The enhancement of electrochemical performance is attributed to the hollow structure and the N,S codoped carbon coating structure, which can reduce the diffusion distance for sodium ions and electrons, alleviate volume expansion during sodium-ion insertion/extraction, and retain the structural integrity effectively. Furthermore, a two-step sodiation processes with FeS2sodiation prior to MnS was demonstrated by X-ray diffraction (XRD), and the electrochemical impedance spectroscopy (EIS) spectra might indicate that the accumulation of the metallic elements in the preconversion reaction can accelerate the transfer of electrons and ions in the further conversion process.