Wang Zhuosen, Shen Jiadong, Xu Xijun, Yuan Jujun, Zuo Shiyong, Liu Zhengbo, Zhang Dechao, Liu Jun
Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou, 450052, China.
Guangdong Provincial Key Laboratory of Advanced Energy Storage Materials, School of Materials Science and Engineering, South China University of Technology, Guangzhou, 510641, P. R. China.
Small. 2022 Apr;18(13):e2106640. doi: 10.1002/smll.202106640. Epub 2022 Feb 10.
Lithium-sulfur (Li-S) batteries have been considered as one of the most promising electrochemical energy storage systems because of their high energy density. However, a series of issues severely limit the practical performances of Li-S batteries such as low conductivity, significant volume change, and shuttle effect. The hollow carbon spheres with huge voids and high electrical conductivity are promising as sulfur hosts. Unfortunately, the nonpolar nature of carbon materials cannot prevent the shuttle effect effectively. In this case, the atomic cobalt is introduced to a nitrogen-doped hollow carbon sphere (ACo@HCS) through polymerization and controlled pyrolysis. The atomic cobalt dopants not only act as active sites to restrict the shuttle effect, but also can promote the kinetics of the sulfur redox reactions. ACo@HCS acting as sulfur host exhibits a high discharge capacity (1003 mAh g ) at a 1.0 C rate after 500 cycles, and the corresponding decay rate is as low as 0.002% per cycle. This exciting work paves a new way to design high-performance Li-S batteries.
锂硫（Li-S）电池因其高能量密度而被认为是最有前途的电化学储能系统之一。然而，一系列问题严重限制了锂硫电池的实际性能，如低导电性、显著的体积变化和穿梭效应。具有巨大孔隙和高导电性的空心碳球有望作为硫宿主。不幸的是，碳材料的非极性性质不能有效地防止穿梭效应。在这种情况下，通过聚合和可控热解将原子钴引入到氮掺杂空心碳球（ACo@HCS）中。原子钴掺杂剂不仅作为活性位点来限制穿梭效应，还可以促进硫氧化还原反应的动力学。作为硫宿主的ACo@HCS在1.0 C倍率下经过500次循环后表现出高放电容量（1003 mAh g），相应的衰减率低至每循环0.002%。这项令人兴奋的工作为设计高性能锂硫电池开辟了一条新途径。
