N, S-Coordinated Co Single Atomic Catalyst Boosting Adsorption and Conversion of Lithium Polysulfides for Lithium-Sulfur Batteries.
N, S-Coordinated Co Single Atomic Catalyst Boosting Adsorption and Conversion of Lithium Polysulfides for Lithium-Sulfur Batteries.
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DOI：
10.1002/smll.202204707
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发表时间：
2022-10
期刊：
影响因子：
13.3
通讯作者：
Kun Liu;Xinyang Wang;Shuai Gu;Huimin Yuan;Feng Jiang;Yingzhi Li;Wen Tan;Qiurong Long
中科院分区：
文献类型：
--
作者：
Kun Liu;Xinyang Wang;Shuai Gu;Huimin Yuan;Feng Jiang;Yingzhi Li;Wen Tan;Qiurong Long
促进多硫化锂向S锂的可逆固-液相转变和抑制多硫化锂从正极到锂负极的穿梭是锂硫电池面临的关键挑战。本文报道了一种用于高性能锂硫电池的具有CoN_3型S结构的亲硫单原子钴离子注入亲锂杂原子-掺杂碳(CaCO@HC)基质。密度泛函理论计算和现场实验表明，优化的CoN_3 S结构能有效地提高锂多硫化物的吸附和氧化还原转化效率。因此，硫负载量为80wt%的S-SACO@HC复合材料在0.05C下的容量为1425.1 mAhg-1，在4 C下的倍率性能为745.9 mAhg-1，并且即使在300次循环后也可以获得680.8 mAhg-1的0.5C容量和低的电解液/硫比(6µL mg-1)。在贫电解液(E/S=4µm L mg-1)和高硫负载量(5.4 mg cm-2)的恶劣条件下，可以获得5.8mAhcm-2的优良面积容量。这项工作有助于加深对锂多硫化物吸附和界面工程的理解，并为解决锂硫电池长期存在的多硫化物穿梭问题提供思路。
Boosting reversible solid-liquid phase transformation from lithium polysulfides to Li2 S and suppressing the shuttling of lithium polysulfides from the cathode to the lithium anode are critical challenges in lithium-sulfur batteries. Here, sulfiphilic single atomic cobalt implanted in lithiophilic heteroatoms-dopped carbon (SACo@HC) matrix with a CoN3 S structure for high-performance lithium-sulfur batteries is reported. Density functional theory calculation and in situ experiments demonstrate that the optimal CoN3 S structure in SACo@HC can effectively improve the adsorption and redox conversion efficiency of lithium polysulfides. Consequently, the S-SACo@HC composite with sulfur loading of 80 wt% delivers a high capacity of 1425.1 mAh g-1 at 0.05 C and outstanding rate performance with 745.9 mAh g-1 at 4 C. Furthermore, a capacity of 680.8 mAh g-1 at 0.5 C with a low electrolyte/sulfur ratio (6 µL mg-1 ) can be achieved even after 300 cycles. With the harsh conditions of lean electrolyte (E/S = 4 µL mg-1 ) and high sulfur loading (5.4 mg cm-2 ), a superior area capacity of 5.8 mAh cm-2 can be obtained. This work contributes to building a profound understanding of the adsorption and interface engineering of lithium polysulfides and provides ideas to tackle the long-standing polysulfide shuttle problem of lithium-sulfur batteries.