A Strategy for Polysulfides/Polyselenides Protection Based on Co9S8@SiO2/C Host in Na‐SeS2 Batteries. (13th May 2020)

• Record Type: Journal Article
• Authors: Yang, Tingting; Qi, Yuruo; Zhong, Wei; Tao, Mengli; Guo, Bingshu; Wu, Yuanke; Bao, Shu‐Juan; Xu, Maowen
• Is Part Of: Advanced functional materials. Volume 31:Number 2(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-05-13
• Subjects: Co9S8@SiO2/C -- hollow sulfides -- Na‐SeS2 batteries -- shuttle effect; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.202001952
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: To obtain unbroken sulfides with delicate morphology from metal–organic frameworks (MOFs), a method for in situ growth of SiO2 protective layers on the surface of MOFs is proposed. This strategy can be successfully expanded to a variety of MOFs (ZIF‐67, Cu‐MOF, ZIF‐8, and PBA). Importantly, room‐temperature Na‐SeS2 batteries with Co9 S8 @SiO2 /C prepared from ZIF‐67 as cathode host are assembled. Due to the hollow structure that can relieve the volume expansion and the co‐adsorption of sodium polysulfides/sodium polyselenides by Co9 S8 @SiO2 /C, the SeS2 /Co9 S8 @SiO2 /C cathode shows excellent rate performance and Coulombic efficiency. In addition, ex situ X‐ray diffraction and in situ Raman results show that S8 and Se8 are generated after the discharge of SeS2, and Se8 is preferentially oxidized during charging. Abstract : A simple, effective, general strategy for the preparation of intact sulfide‐based hollow structures from metal–organic frameworks is presented. Benefiting from the structural and compositional advantages, the SeS2 /Co9 S8 @SiO2 /C composite cathode shows excellent electrochemical performance.