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Research Article

Three-dimensionally ordered, ultrathin graphitic-carbon frameworks with cage-like mesoporosity for highly stable Li-S batteries

Huijuan Yu1,2,§, Hanwen Li1,2,§, Shouyi Yuan1, Yuchi Yang1,2, Jiahui Zheng1,2, Jianhua Hu2, Dong Yang2( ), Yonggang Wang1( ), Angang Dong1( )
Collaborative Innovation Center of Chemistry for Energy MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative Materials, and Department of Chemistry, Fudan UniversityShanghai200433China
State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science, Fudan UniversityShanghai200433China

§ These authors contributed equally to this work.

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Graphical Abstract

Abstract

Mesoporous carbons have been widely utilized as the sulfur host for lithium-sulfur (Li-S) batteries. The ability to engineer the porosity, wall thickness, and graphitization degree of the carbon host is essential for addressing issues that hamper commercialization of Li-S batteries, such as fast capacity decay and poor high-rate performance. In this work, highly ordered, ultrathin mesoporous graphitic-carbon frameworks (MGFs) having unique cage-like mesoporosity, derived from self-assembled Fe3O4 nanoparticle superlattices, are demonstrated to be an excellent host for encapsulating sulfur. The resulting S@MGFs exhibit high specific capacity (1, 446 mAh·g-1 at 0.15 C), good rate capability (430 mAh·g-1 at 6 C), and exceptional cycling stability (~0.049% capacity decay per cycle at 1 C) when used as Li-S cathodes. The superior electrochemical performance of the S@MGFs is attributed to the many unique and advantageous structural features of MGFs. In addition to the interconnected, ultrathin graphitic-carbon framework that ensures rapid electron and lithium-ion transport, the microporous openings between adjacent mesopores efficiently suppress the diffusion of polysulfides, leading to improved capacity retention even at high current densities.

Keywords

self-assemblynanoparticlesgraphene frameworkscage-like mesoporosityLi-S batteries

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Nano Research
Volume 10 Issue 7,
July 2017
Pages 2495-2507
DOI: 10.1007/s12274-017-1454-1
Cite this article:
Yu H, Li H, Yuan S, et al. Three-dimensionally ordered, ultrathin graphitic-carbon frameworks with cage-like mesoporosity for highly stable Li-S batteries. Nano Research, 2017, 10(7): 2495-2507. https://doi.org/10.1007/s12274-017-1454-1

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Received: 05 November 2016
Revised: 12 December 2016
Accepted: 01 January 2017
Published: 04 April 2017
© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2017
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