Efficient Polysulfide Trapping and Conversion on N‐Doped CoTe2 via Enhanced Dual‐Anchoring Effect. Issue 42 (14th September 2021)

• Record Type: Journal Article
• Authors: Song, Xueqin; Tian, Da; Qiu, Yue; Sun, Xun; Jiang, Bo; Zhao, Chenghao; Zhang, Yu; Xu, Xianzhu; Fan, Lishuang; Zhang, Naiqing
• Is Part Of: Small. Volume 17:Issue 42(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-14
• Subjects: dual‐anchoring effect -- electrocatalysis -- lithium–sulfur batteries -- polysulfide redox reaction -- shuttle effect; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202102962
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Polysulfide shuttling and sluggish sulfur redox kinetics hinder the cyclability and rate capability of lithium–sulfur (Li–S) batteries. The intrinsic redox kinetics of sulfur cathodes strongly depends on the interaction between catalysts and sulfur species. Herein, N‐doped CoTe2 is proposed as an effective dual‐anchoring electrocatalyst, which can simultaneously bind Li and S atoms in lithium polysulfides via ionic Te–Li/N–Li bonding and coordinate covalent Co–S bonding. The incorporated N not only serves as enhanced lithiophilic site, but also an agent to improve the sulfiphilicity of the Co site as revealed by a series of experimental and computational results. Benefiting from these superiorities, the use of N‐doped CoTe2 as a catalytic interlayer enables efficient operation of Li–S batteries in terms of impressive rate capability of 758 mAh g −1 at 4 C and very low capacity decay of 0.021% per cycle over 1000 cycles. The material and strategy demonstrated in this work may open the door toward developing more advanced Li–S electrocatalysts. Abstract : Dual‐anchoring materials capable of anchoring both S and Li atoms exhibit excellent lithium polysulfide adsorption and catalysis capability. Gathering cooperative lithiophilic and sulfiphilic interactions in a single‐phase catalyst can extend the dual‐anchoring property to the whole surface. Herein, N‐doped CoTe2 with lithiophilic Te/N atoms and sulfiphilic Co atoms is presented to trap lithium polysulfides and boost their redox kinetics.