Sun Lin, Liu Yanxiu, Xie Jie, Zhang Feng, Jiang Ruiyu, Jin Zhong
State Key Laboratory of Coordination Chemistry, MOE Key Laboratory of Mesoscopic Chemistry, MOE Key Laboratory of High Performance Polymer Materials and Technology, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province, School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng 224051, China.
ACS Appl Mater Interfaces. 2024 Mar 13;16(10):12907-12915. doi: 10.1021/acsami.3c15984. Epub 2024 Feb 27.
The practical application of Li-S batteries (LSBs) has long been impeded by the inefficient utilization of sulfur and slow kinetics. Utilizing conductive carbonaceous frameworks as a host scaffold presents an efficient and cost-effective approach to enhance sulfur utilization for redox reactions in LSBs. However, the interaction of pure carbon materials with lithium polysulfide intermediates (LiPSs) is limited to weak van der Waals forces. Hence, the development of an economical method for synthesizing heteroatom-doped carbon materials for sulfur fixation is of paramount importance. In this study, we introduce a hierarchical porous nitrogen-doped carbon sponge (NPCS) with an exceptionally high BET surface area of 3182.2 m g, achieved through a facile template-assisted polymerization method. The incorporation of inorganic salts, free radical polymerization, and deuteric freeze-drying techniques facilitates the formation of hierarchical pores within the NPCS. After sulfur fixation, the resulting S/NPCS electrode demonstrates remarkable electrochemical performance in LSBs. Specifically, it achieves an 80% sulfur utilization rate, maintains a high reversible specific capacity of 400 mA h g even after 600 cycles at a demanding current density of 5.0 A g, and exhibits superior rate capability. It is believed that this work will inspire the rational design of cost-effective carbon-based electrodes for high-performance LSBs.
锂硫电池（LSBs）的实际应用长期以来一直受到硫利用效率低下和动力学缓慢的阻碍。利用导电碳质骨架作为主体支架，是一种提高LSBs中氧化还原反应硫利用率的高效且经济有效的方法。然而，纯碳材料与多硫化锂中间体（LiPSs）之间的相互作用仅限于微弱的范德华力。因此，开发一种经济的方法来合成用于固定硫的杂原子掺杂碳材料至关重要。在本研究中，我们通过一种简便的模板辅助聚合法，引入了一种具有3182.2 m² g超高比表面积的分级多孔氮掺杂碳海绵（NPCS）。无机盐的加入、自由基聚合和氘代冷冻干燥技术促进了NPCS中分级孔的形成。在固定硫之后，所得的S/NPCS电极在LSBs中表现出卓越的电化学性能。具体而言，它实现了80%的硫利用率，即使在5.0 A g的苛刻电流密度下循环600次后仍保持400 mA h g的高可逆比容量，并展现出优异的倍率性能。相信这项工作将激发人们合理设计用于高性能LSBs的经济高效的碳基电极。
