In situ transformation of LDH into hollow cobalt-embedded and N-doped carbonaceous microflowers as polysulfide mediator for lithium-sulfur batteries
In situ transformation of LDH into hollow cobalt-embedded and N-doped carbonaceous microflowers as polysulfide mediator for lithium-sulfur batteries
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DOI：
10.1016/j.cej.2019.123457
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发表时间：
2020-04
影响因子：
15.1
通讯作者：
Shixia Chen;Xinxin Han;Junhui Luo;Jing Liao;Jun Wang;Q. Deng;Zheling Zeng;S. Deng
中科院分区：
文献类型：
--
作者：
Shixia Chen;Xinxin Han;Junhui Luo;Jing Liao;Jun Wang;Q. Deng;Zheling Zeng;S. Deng
可溶性多硫化锂（LiPS）的穿梭效应以及缓慢的氧化还原动力学严重阻碍了锂硫（Li-S）电池的应用。在此，通过间苯阴离子插层Co-Al层状双氢氧化物（CoAl LDHs）的原位转化制备了一种新型空心钴嵌入氮掺杂碳质微花（H-Co-NCM）。所得的 S@H-Co-NCM 电极表现出优异的电催化性能，可提高 LiPSs 转化和 Li2S 成核的动力学。因此，具有82％高硫负载量的组装Li-S电池在0.1C下表现出1374mAhg−1的显着初始容量、优异的倍率性能（2C下611mAhg−1）和出色的循环稳定性（0.5C下500次循环后的循环衰减率为0.069％）。 LiPS的强化学吸附和快速转化的综合策略为抑制穿梭效应提供了更深入的见解。
The shuttle effect of soluble lithium polysulfides (LiPSs), accompanying with sluggish redox kinetics has severely impeded the implementation of lithium-sulfur (Li-S) batteries. Herein, a novel hollow cobalt-embedded and nitrogen-doped carbonaceous microflower (H-Co-NCM) is fabricated viain situtransformation of metanilic anions intercalated Co-Al layered double hydroxides (CoAl LDHs). The as-obtained S@H-Co-NCM electrode exhibits superior electrocatalytic performances to boost the kinetics of LiPSs conversion and Li2S nucleation. Consequently, the assembled Li-S batteries with a high sulfur loading of 82% display a remarkable initial capacity of 1374 mAh g−1at 0.1 C, excellent rate capability (611 mAh g−1at 2 C), and superb cycle stability (cyclic decay rate of 0.069% over 500 cycles at 0.5 C). The integrated strategy of strong chemisorption and fast conversion of LiPSs provides deeper insights to suppress the shuttle effect.