Construction of Ni/Ni3N heterojunctions as reversible micro-reaction centers for lithium polysulfides. Issue 32 (2nd August 2022)

• Record Type: Journal Article
• Authors: Xiao, Tingjiao; Yi, Fengjin; Wang, He; Yang, Mingzhi; Liu, Weiliang; Ren, Manman; Zhang, Xu; Zhou, Zhen
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 32(2022)
• Page Start: 16866
• Page End: 16872
• Publication Date: 2022-08-02
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2ta04095f
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : The synergetic effect of the Ni/Ni3 N heterojunctions and N-doped carbon nanotubes endows the Ni/Ni3 N–CNT/S electrode with satisfactory electrochemical performance in Li–S batteries. Abstract : Lithium–sulfur batteries (LSBs) are one of the most promising next-generation energy storage systems. However, some intractable issues such as "shuttle effect", low electronic conductivity and large volume change of the S cathode seriously limit their application. In this work, a composite of Ni/Ni3 N heterojunction-decorated hollow carbon nanotubes (Ni/Ni3 N–CNT) was fabricated and used as a sulfur host, meanwhile, the mechanism of Ni/Ni3 N heterojunctions in inhibiting the shuttle effect of lithium polysulfides (LiPSs) was investigated in detail. Density functional theory (DFT) calculations and experimental conclusions reveal that the Ni/Ni3 N heterojunctions promote the nucleation and growth of Li2 S2 /Li2 S and accelerate the redox process of LiPSs. Consequently, the Ni/Ni3 N–CNT/S electrode demonstrates satisfactory electrochemical performance. It delivers a superior reversible capacity of 643.3 mA h g −1 at 5C rate with an average decay rate of 0.10% per cycle over 400 cycles. Besides it can present a specific capacity of 439.7 mA h g −1 with a high S loading of 5.0 mg cm −2 after 100 cycles. Most importantly, this work proposes a simple method for the preparation of Ni/Ni3 N heterostructures which can be used as reversible catalytic micro-reaction centers for LiPSs. In particular, our results will provide an experimental and theoretical basis for the application of other metal/metal nitride heterostructures in LSBs.