Details

Autor(en) / Beteiligte

• Hu, Shunyou
• Huang, Xueyan
• Zhang, Ling
• Li, Guanglei
• Chen, Shengmin
• Zhang, Jiaheng
• Liu, Xiangli

Titel

Vacancy‐Defect Topological Insulators Bi2Te3−x Embedded in N and B Co‐Doped 1D Carbon Nanorods Using Ionic Liquid Dopants for Kinetics‐Enhanced Li–S Batteries

Ist Teil von

• Advanced functional materials, 2023-05, Vol.33 (20), p.n/a

Ort / Verlag

Hoboken: Wiley Subscription Services, Inc

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Lithium–sulfur (Li–S) batteries are hindered by the shuttle effect and the sluggish redox kinetics of polysulfides. In this study, topological insulators (TIs) Bi2Te3−x with abundant Te vacancies embedded in N and B co‐doped carbon nanorods (Bi2Te3−x@NBCNs) are synthesized and used as sulfur host composites for high‐performance Li–S batteries. Bi2Te3−x@NBCNs effectively enhance the intrinsic conductivity, strengthened the chemical affinity, and accelerated the redox kinetics of polysulfides. 1D carbon nanorods with N and B co‐doped heteroatoms endowed with abundant polar sites improve the chemical affinity of polysulfides, while the embedded Bi2Te3−x nanoparticles further promote the nucleation and electrodeposition of Li2S2/Li2S. In situ Raman spectroscopy confirms that Bi2Te3−x@NBCNs effectively reduced cathode‐side accumulation of polysulfides and suppressed the shuttle effect. Owing to the extraordinary synergistic effects of rich heteroatom polar sites and conductive topological surface states, Bi2Te3−x@NBCN‐based cells exhibit a high initial specific capacity of 1264 mAh g−1 at 0.2 C and ultra‐long lifetime (>1000 cycles, with a degradation rate of 0.02% per cycle at 1.0 C). The fundamental insights offered by this work are likely to enable improvement of the electrochemical performance of Li–S batteries based on TI materials. A topological insulator Bi2Te3−x with conductive topological surface states and abundant Te vacancies embedded in N, B co‐doped 1D carbon nanorods (Bi2Te3−x@NBCNs) with ultrathin carbon layers is synthesized and served as sulfur host composites for the high‐performance Li–S batteries. The catalysts can reduce the activation energies of the heterogenous reactions, especially for the nucleation and deposition of Li2S.