P-Doped NiTe2 with Te-Vacancies in Lithium-Sulfur Batteries Prevents Shuttling and Promotes Polysulfide Conversion

Weiqi Yao; Chengxiang Tian; Chao Yang; Jie Xu; Yufeng Meng; Ingo Manke; Nan Chen; Ziling Wu; Liang Zhan; Yanli Wang; Renjie Chen

doi:10.1002/adma.202106370

P-Doped NiTe₂ with Te-Vacancies in Lithium-Sulfur Batteries Prevents Shuttling and Promotes Polysulfide Conversion

Adv Mater. 2022 Mar;34(11):e2106370. doi: 10.1002/adma.202106370. Epub 2022 Feb 3.

Authors

Weiqi Yao¹, Chengxiang Tian², Chao Yang³, Jie Xu¹, Yufeng Meng⁴, Ingo Manke³, Nan Chen⁵, Ziling Wu¹, Liang Zhan¹, Yanli Wang¹, Renjie Chen⁵

Affiliations

¹ State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China.
² Department of Mechanical Engineering, National University of Singapore, Singapore, 117575, Singapore.
³ Helmholtz Centre Berlin for Materials and Energy, Hahn-Meitner-Platz 1, 14109, Berlin, Germany.
⁴ Shanghai Institute of Space Power Sources, Shanghai, 200245, China.
⁵ Beijing Key Laboratory of Environmental Science and Engineering, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.

PMID: 35019192
DOI: 10.1002/adma.202106370

Abstract

Lithium-sulfur (Li-S) batteries have been hindered by the shuttle effect and sluggish polysulfide conversion kinetics. Here, a P-doped nickel tellurium electrocatalyst with Te-vacancies (P⊂NiTe_2- _x ) anchored on maize-straw carbon (MSC) nanosheets, served as a functional layer (MSC/P⊂NiTe_2- _x ) on the separator of high-performance Li-S batteries. The P⊂NiTe_2- _x electrocatalyst enhanced the intrinsic conductivity, strengthened the chemical affinity for polysulfides, and accelerated sulfur redox conversion. The MSC nanosheets enabled NiTe₂ nanoparticle dispersion and Li⁺ diffusion. In situ Raman and ex situ X-ray absorption spectra confirmed that the MSC/P⊂NiTe_2- _x restrained the shuttle effect and accelerated the redox conversion. The MSC/P⊂NiTe_2- _x -based cell has a cyclability of 637 mAh g^-1 at 4 C over 1800 cycles with a degradation rate of 0.0139% per cycle, high rate performance of 726 mAh g^-1 at 6 C, and a high areal capacity of 8.47 mAh cm^-2 under a sulfur configuration of 10.2 mg cm^-2 , and a low electrolyte/sulfur usage ratio of 3.9. This work demonstrates that vacancy-induced doping of heterogeneous atoms enables durable sulfur electrochemistry and can impact future electrocatalytic designs related to various energy-storage applications.

Keywords: P-doping; Te-vacancy; electrocatalysts; lithium-sulfur batteries; modified separator.

Abstract

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