Heteroatomic TexS1-x molecule/C nanocomposites as stable cathode materials in carbonate-based electrolytes for lithium-chalcogen batteries
Heteroatomic TexS1-x molecule/C nanocomposites as stable cathode materials in carbonate-based electrolytes for lithium-chalcogen batteries
复制标题
杂原子 TexS1-x 分子/C 纳米复合材料作为锂硫属电池碳酸酯基电解质中稳定的正极材料
DOI：
10.1039/c8ta02751j
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发表时间：
2018-06-07
影响因子：
11.9
通讯作者：
Zhou, Lang
中科院分区：
文献类型：
--
作者：
Sun, Fugen;Zhang, Bo;Zhou, Lang
通过熔融浸渍的方法，将杂原子tex1 -x分子均匀地包裹在有序的介孔碳CMK-3中，成功地制备了一种稳定的高能锂-锂电池用碳酸基电解质正极材料。杂原子TexS1-x分子中的Te-S键使其具有比同原子S-8分子更高的本禀电导率和与Li的电化学反应活性。此外，含te的多硫族化合物中间体可以在碳酸盐基电解质的TexS1-x/CMK-3表面诱导形成固体电解质界面（SEI）层，有效地防止了多硫族化合物与碳酸盐溶剂的穿梭效应和副反应。在CMK-3介孔约束下，tex1 -x/CMK-3复合材料可以在碳酸盐基电解质中可逆充放电，具有长循环稳定性和高倍率性能。因此，最佳Te/S摩尔比为1/9的Te0.1S0.9/CMK-3复合材料在250 mA g（-1）下循环100次后保持845 mA h g（-1）的高可逆容量，在1 mA g（-1）下循环500次后保持485 mA h g（-1）的高可逆容量。这些令人鼓舞的结果表明，杂原子TexS1-x分子/C复合材料有望成为长循环寿命和高功率密度锂电池的正极材料。
A stable cathode material in a conventional carbonate-based electrolyte for high-energy lithium-chalcogen batteries was successfully fabricated by homogeneously confining heteroatomic TexS1-x molecules into ordered mesoporous carbon CMK-3 via a facile melt-impregnation route. The Te-S bonds in the heteroatomic TexS1-x molecules endow them with higher intrinsic electrical conductivity and electrochemical reaction activity with Li than the homoatomic S-8 molecules. Moreover, Te-containing polychalcogenide intermediates could induce the formation of solid electrolyte interphase (SEI) layers on the TexS1-x/CMK-3 surfaces in the carbonate-based electrolyte, which efficiently prevent polychalcogenides from the shuttle effect and side reactions with the carbonate solvent. With further assistance of mesopore confinement of CMK-3, the TexS1-x/CMK-3 composites can be reversibly charged and discharged in the carbonate-based electrolyte with long cycling stability and high rate capability. Therefore, the Te0.1S0.9/CMK-3 composite with an optimal Te/S mole ratio of 1/9 maintains high reversible capacities of 845 mA h g(-1) after 100 cycles at 250 mA g(-1) and 485 mA h g(-1) after 500 cycles at 1 A g(-1). These encouraging results suggest that the heteroatomic TexS1-x molecule/C composite could be a promising cathode material for long cycle life and high power density lithium batteries.