Details

Autor(en) / Beteiligte

• Ye, Chao
• Jiao, Yan
• Chao, Dongliang
• Ling, Tao
• Shan, Jieqiong
• Zhang, Binwei
• Gu, Qinfen
• Davey, Kenneth
• Wang, Haihui
• Qiao, Shi‐Zhang

Titel

Electron‐State Confinement of Polysulfides for Highly Stable Sodium–Sulfur Batteries

Ist Teil von

• Advanced materials (Weinheim), 2020-03, Vol.32 (12), p.e1907557-n/a

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2020

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Confinement of polysulfides in sulfur cathodes is pivotal for eliminating the “shuttle effect” in metal–sulfur batteries, which represent promising solutions for large‐scale and sustainable energy storage. However, mechanistic exploration and in‐depth understanding for the confinement of polysulfides remain limited. Consequently, it is a critical challenge to achieve highly stable metal–sulfur batteries. Here, based on a 2D metal–organic framework (2D MOF), a new mechanism to realize effective confinement of polysulfides is proposed. A combination of in situ synchrotron X‐ray diffraction, electrochemical measurements, and theoretical computations reveal that the dynamic electron states of the Ni centers in the 2D MOF enable the interaction between polysulfides and the MOF in the discharge/charge process to be tuned, resulting in both strong adsorption and fast conversion kinetics of polysulfides. The resultant room‐temperature sodium–sulfur batteries are amongst the most stable reported so far, thus demonstrating that the new mechanism opens a promising avenue for the development of high‐performance metal–sulfur batteries. 2D Ni‐based metal–organic frameworks (MOFs) are synthesized as cathode materials for room‐temperature sodium–sulfur batteries. The dynamic electron states of the Ni centers facilitate the adsorption and conversion of the polysulfides, which originate from the charge redistribution process during exfoliation of the bulk MOFs. This results in significantly high electrochemical performance and can be applied to address the shuttle effect in metal–sulfur batteries.