An ordered conductive Ni-CAT nanorods array as all-round polysulfide regulator for lithium-sulfur batteries

• Published in: Electrochimica acta Vol. 441; p. 141788
• Main Authors: Wang, Yanan, Zhao, Jiangyuan, Wu, Feichao, Wei, Shuaichong, Cao, Shuyi, Yang, Yanqin, Li, Jingde
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 10.02.2023
• Subjects: Lithium-sulfur batteries; Nanorods array; Ni-CAT; Polysulfide regulator; Nanorods array; Lithium-sulfur batteries; Polysulfide regulator; Ni-CAT
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2022.141788

•An ordered conductive Ni-CAT nanorods array is prepared on carbon nanotube film.•The Ni-CAT nanorods array is used as a full featured interlayer material.•The interlayer adsorbs and blocks polysulfides, and catalyzes their conversion.•The resulting Li-S batteries exhibit excellent cycle and rate performances. The effective suppression of polysulfide shuttle is indispensable for the commercialization of lithium-sulfur batteries (LSBs). In this work, an ordered conductive metal-organic framework (MOF) Ni-CAT nanorods array rooted on carbon nanotube film (Ni-CAT/CNTF) is proposed for this subject. The well-aligned MOF nanorods array possesses a unique vertical structure, presenting an incompact upper part and dense root, which guarantee the highly efficient adsorption and selective sieving towards polysulfides, respectively, as well as a fast Li+ transfer. What's more, the good electrical property and fully exposed Ni-based catalytic sites are qualified to boost the electrochemical kinetics. Consequently, LSBs with this fully functional MOF nanorods array exhibit an astonishing capacity of 1087 mAh g−1 and an extraordinary cyclability with a finite capacity-fading of only 0.026% per cycle for 1000 cycles at 1 C, along with an exceptional rate performance of 754 mAh g−1 at 5 C. Moreover, outstanding cycle and rate performance can be maintained under elevated sulfur loadings with a reduced electrolyte content. This work offers new insights into the rational design of polyfunctional nanostructures in LSBs. [Display omitted]