Nano-Micro Letters ( IF 26.6 ) Pub Date : 2022-06-17 , DOI: 10.1007/s40820-022-00873-x Yinger Xiang 1 , Laiqiang Xu 1 , Li Yang 2 , Yu Ye 1 , Zhaofei Ge 1 , Jiae Wu 1 , Wentao Deng 1 , Guoqiang Zou 1 , Hongshuai Hou 1 , Xiaobo Ji 1, 3
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Highlights
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The chemical process of local oxidation–partial reduction–deep coupling for stibnite reduction of carbon dots (CDs) is revealed by in-situ high-temperature X-ray diffraction.
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Sb2S3@xCDs anode delivers high initial coulombic efficiency in lithium ion batteries (85.2%) and sodium ion batteries (82.9%), respectively.
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C–S bond influenced by oxygen-rich carbon matrix can restrain the conversion of sulfur to sulfite, well confirmed by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations.
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CDs-induced Sb–O–C bond is proved to effectively regulate the interfacial electronic structure.
Abstract
The application of Sb2S3 with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency (ICE). In this work, natural stibnite modified by carbon dots (Sb2S3@xCDs) is elaborately designed with high ICE. Greatly, chemical processes of local oxidation–partial reduction–deep coupling for stibnite reduction of CDs are clearly demonstrated, confirmed with in situ high-temperature X-ray diffraction. More impressively, the ICE for lithium-ion batteries (LIBs) is enhanced to 85%, through the effect of oxygen-rich carbon matrix on C–S bonds which inhibit the conversion of sulfur to sulfite, well supported by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations. Not than less, it is found that Sb–O–C bonds existed in the interface effectively promote the electronic conductivity and expedite ion transmission by reducing the bandgap and restraining the slip of the dislocation. As a result, the optimal sample delivers a tremendous reversible capacity of 660 mAh g−1 in LIBs at a high current rate of 5 A g−1. This work provides a new methodology for enhancing the electrochemical energy storage performance of metal sulfides, especially for improving the ICE.
中文翻译：
用于锂/钠离子电池的天然辉锑矿：碳点引发高初始库仑效率
强调
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通过原位高温 X 射线衍射揭示了碳点 (CD) 辉锑矿还原的局部氧化-部分还原-深度耦合的化学过程。
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Sb 2 S 3 @xCDs 阳极分别在锂离子电池 (85.2%) 和钠离子电池 (82.9%) 中提供高初始库仑效率。
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受富氧碳基质影响的 C-S 键可以抑制硫向亚硫酸盐的转化，固体电解质界面层的 X 射线光电子能谱表征有助于密度泛函理论计算，很好地证实了这一点。
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CDs诱导的Sb-O-C键被证明可以有效地调节界面电子结构。
抽象的
具有惊人理论容量的Sb 2 S 3在碱金属离子电池中的应用受到其较差的导电性和较低的初始库仑效率（ICE）的严重限制。在这项工作中，碳点修饰的天然辉锑矿 (Sb 2 S 3@xCDs）精心设计，ICE高。重要的是，通过原位高温 X 射线衍射证实了局部氧化 - 部分还原 - 深度耦合用于还原 CDs 辉锑矿的化学过程。更令人印象深刻的是，通过富氧碳基质对抑制硫转化为亚硫酸盐的 C-S 键的影响，锂离子电池 (LIB) 的 ICE 提高到 85%，这得到了 X 射线光电子能谱的充分支持固体电解质界面层的表征有助于密度泛函理论计算。不少于此，发现界面中存在的Sb-O-C键通过减小带隙和抑制位错的滑移有效地促进电子导电并加快离子传输。因此，-1在 LIB 中以 5 A g -1的高电流速率。这项工作为提高金属硫化物的电化学储能性能，特别是改善 ICE 提供了一种新的方法。
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