Saeedi Garakani Sadaf, Xie Dongjiu, Kheirabad Atefeh Khorsand, Lu Yan, Yuan Jiayin
Department of Materials and Environmental Chemistry, Stockholm University Stockholm 10691 Sweden
Department for Electrochemical Energy Storage, Helmholtz-Zentrum Berlin für Materialien und Energie Hahn-Meitner Platz 1 Berlin 14109 Germany
Mater Adv. 2021 Jun 25;2(15):5203-5212. doi: 10.1039/d1ma00441g. eCollection 2021 Aug 2.
This study deals with the facile synthesis of Fe S nanoparticle-containing nitrogen-doped porous carbon membranes (denoted as Fe S/N-PCMs) vacuum carbonization of hybrid porous poly(ionic liquid) (PIL) membranes, and their successful use as a sulfur host material to mitigate the shuttle effect in lithium-sulfur (Li-S) batteries. The hybrid porous PIL membranes as the sacrificial template were prepared ionic crosslinking of a cationic PIL with base-neutralized 1,1'-ferrocenedicarboxylic acid, so that the iron source was molecularly incorporated into the template. The carbonization process was investigated in detail at different temperatures, and the chemical and porous structures of the carbon products were comprehensively analyzed. The Fe S/N-PCMs prepared at 900 °C have a multimodal pore size distribution with a satisfactorily high surface area and well-dispersed iron sulfide nanoparticles to physically and chemically confine the LiPSs. The sulfur/Fe S/N-PCM composites were then tested as electrodes in Li-S batteries, showing much improved capacity, rate performance and cycle stability, in comparison to iron sulfide-free, nitrogen-doped porous carbon membranes.
本研究通过混合多孔聚离子液体（PIL）膜的真空碳化，实现了含FeS纳米颗粒的氮掺杂多孔碳膜（记为FeS/N-PCMs）的简便合成，并成功将其用作硫宿主材料，以减轻锂硫（Li-S）电池中的穿梭效应。作为牺牲模板的混合多孔PIL膜是通过阳离子PIL与碱中和的1,1'-二茂铁二甲酸进行离子交联制备的，从而使铁源分子掺入模板中。详细研究了不同温度下的碳化过程，并对碳产物的化学结构和多孔结构进行了全面分析。在900℃制备的FeS/N-PCMs具有多峰孔径分布，具有令人满意的高比表面积和分散良好的硫化铁纳米颗粒，可物理和化学地限制多硫化锂。然后将硫/FeS/N-PCM复合材料作为电极在Li-S电池中进行测试，与不含硫化铁的氮掺杂多孔碳膜相比，其容量、倍率性能和循环稳定性都有显著提高。
