title: Refined Sulfur Nanoparticles Immobilized in Metal-Organic Polyhedron as Stable Cathodes for Li-S Battery.
abstract: The lithium-sulfur (Li-S) battery presents a promising rechargeable energy storage technology for the increasing energy demand in a worldwide range. However, current main challenges in Li-S battery are structural degradation and instability of the solid-electrolyte interphase caused by the dissolution of polysulfides during cycling, resulting in the corrosion and loss of active materials. Herein, we developed novel hybrids by employing metal-organic polyhedron (MOP) encapsulated PVP-functionalized sulfur nanoparticles (S@MOP), where the active sulfur component was efficiently encapsulated within the core of MOP and PVP as a surfactant was helpful to stabilize the sulfur nanoparticles and control the size and shape of corresponding hybrids during their syntheses. The amount of sulfur embedded into MOP could be controlled according to requirements. By using the S@MOP hybrids as cathodes, an obvious enhancement in the performance of Li-S battery was achieved, including high specific capacity with good cycling stability. The MOP encapsulation could enhance the utilization efficiency of sulfur. Importantly, the structure of the S@MOP hybrids was very stable, and they could last for almost 1000 cycles as cathodes in Li-S battery. Such high performance has rarely been obtained using metal-organic framework systems. The present approach opens up a promising route for further applications of MOP as host materials in electrochemical and energy storage fields.
authors.forename: Linyi
authors.initials: L
authors.lastname: Bai
authors.forename: Dongliang
authors.initials: D
authors.lastname: Chao
authors.forename: Pengyao
authors.initials: P
authors.lastname: Xing
authors.forename: Li Juan
authors.initials: LJ
authors.lastname: Tou
authors.forename: Zhen
authors.initials: Z
authors.lastname: Chen
authors.forename: Avijit
authors.initials: A
authors.lastname: Jana
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798.
authors.forename: Ze Xiang
authors.initials: ZX
authors.lastname: Shen
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Zhao
keywords: encapsulation; lithium−sulfur battery; metal−organic polyhedron; porous materials; sulfur nanoparticles