title: Amylose-Derived Macrohollow Core and Microporous Shell Carbon Spheres as Sulfur Host for Superior Lithium-Sulfur Battery Cathodes.
abstract: Porous carbon can be tailored to great effect for electrochemical energy storage. In this study, we propose a novel structured spherical carbon with a macrohollow core and a microporous shell derived from a sustainable biomass, amylose, by a multistep pyrolysis route without chemical etching. This hierarchically porous carbon shows a particle distribution of 2-10 μm and a surface area of 672 m2g-1. The structure is an effective host of sulfur for lithium-sulfur battery cathodes, which reduces the dissolution of polysulfides in the electrolyte and offers high electrical conductivity during discharge/charge cycling. The hierarchically porous carbon can hold 48 wt % sulfur in its porous structure. The S@C hybrid shows an initial capacity of 1490 mAh g-1and retains a capacity of 798 mAh g-1after 200 cycles at a discharge/charge rate of 0.1 C. A capacity of 487 mAh g-1is obtained at a rate of 3 C. Both a one-step pyrolysis and a chemical-reagent-assisted pyrolysis are also assessed to obtain porous carbon from amylose, but the obtained carbon shows structures inferior for sulfur cathodes. The multistep pyrolysis and the resulting hierarchically porous carbon offer an effective approach to the engineering of biomass for energy storage. The micrometer-sized spherical S@C hybrid with different sizes is also favorable for high-tap density and hence the volumetric density of the batteries, opening up a wide scope for practical applications.
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Xuanbing
authors.initials: X
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Mingxia
authors.identifier: http://orcid.org/0000-0002-4719-6747
authors.initials: M
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Dawei
authors.initials: D
authors.lastname: Ren
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Yongfeng
authors.identifier: http://orcid.org/0000-0002-4002-8265
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Chemistry, University College London , London WC1H 0AJ, United Kingdom.
authors.forename: Zhengxiao
authors.initials: Z
authors.lastname: Guo
authors.affiliation: School of Environmental Sciences, University of East Anglia , Norwich NR4 7TJ, United Kingdom.
authors.forename: Congxiao
authors.initials: C
authors.lastname: Shang
authors.affiliation: Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials, Guangxi Key Laboratory of Information Material, School of Materials Science and Engineering, Guilin University of Electronic Technology , Guilin 541004, PR China.
authors.forename: Lixian
authors.initials: L
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Silicon Materials, Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province & School of Materials Science and Engineering, Zhejiang University , Hangzhou 310027, PR China.
authors.forename: Hongge
authors.initials: H
authors.lastname: Pan
keywords: amylose; biomass material; electrochemical performance; lithium−ion batteries; sulfur cathode