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论文类型：期刊论文

发表时间：2013-03-27

发表刊物：ACS APPLIED MATERIALS & INTERFACES

收录刊物：SCIE、EI、PubMed、ESI高被引论文、Scopus

卷号：5

期号：6

页面范围：2208-2213

ISSN号：1944-8244

关键字：lithium-sulfur battery; peapodlike mesoporous carbon; carbon/sulfur composite; large pore volume; high sulfur loading cathode

摘要：Porous carbon materials with large pore volume are crucial in loading insulated sulfur with the purpose of achieving high performance for lithium-sulfur batteries. In our study, peapodlike mesoporous carbon with interconnected pore channels and large pore volume (4.69 cm(3) g(-1)) was synthesized and used as the matrix to fabricate carbon/sulfur (C/S) composite which served as attractive cathodes for lithium-sulfur batteries. Systematic investigation of the C/S composite reveals that the carbon matrix can hold a high but suitable sulfur loading of 84 wt %, which is beneficial for improving the bulk density in practical application. Such controllable sulfur-filling also effectively allows the volume expansion of active sulfur during Li+ insertion. Moreover, the thin carbon walls (3-4 nm) of carbon matrix not only are able to shorten the pathway of Li+ transfer and conduct electron to overcome the poor kinetics of sulfur cathode, but also are flexible to warrant structure stability. Importantly, the peapodlike carbon shell is beneficial to increase the electrical contact for improving electronic conductivity of active sulfur. Meanwhile, polymer modification with polypyrrole coating layer further restrains polysulfides dissolution and improves the cycle stability of carbon/sulfur composites.