Sulfide-based MOF material modification of separators: enhancing performance of lithium-sulfur batteries by suppressing shuttle effect

ABSTRACT

Lithium-sulfur batteries (LSBs) are extensively studied owing to their high theoretical capacity and low cost. However, the shuttle effect of lithium-sulfur batteries hinders their development. In this study, we obtained a modified separator to inhibit the shuttle effect through physical and chemical adsorption. The CoS₂ nanosheets (CSN_S) derived from a cobalt-based metal-organic framework (Co-MOF) were synthesized by a simple two-step method involving hydrothermal sulfurization and thermal decomposition. The material was then coated onto a Polypropylene (PP) separator using vacuum filtration and assembled into a LSB for systematic testing and research of its electrochemical performance and mechanism. Thanks to the intrinsic polarity of the CSNs and more active sites brought by the Co-MOF material, the modified separator has strong chemical adsorption and catalytic effects on polysulfides, anchoring and accelerating their conversion. When using the CSNs-PP separator, the LSB achieved a high initial capacity of 1002.4 mAh g⁻¹ at 1 C, with only a 0.099% decay per cycle after 500 cycles. The modified separator effectively alleviating the shuttle effect, reducing internal resistance, weakening reaction polarization, and improving the specific capacity, stability, and reversibility of the battery.

KEYWORDS:

• Lithium-sulfur batteries
• shuttle effect
• modified separator
• Co-MOF material
• CoS₂ nanosheets

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/15567036.2024.2310741

Additional information

Funding

This work is financially supported by the National Natural Science Foundation of China, China (No.21676148), and the Fundamental Research Funds for the Central Universities, China (No.30918012202).

Notes on contributors

Xuefei Liu

Xuefei Liu works at China Construction Eighth Bureau Fourth Construction Co., Ltd.

Xiaotong Gao

Xiaotong Gao is a master’s student at Nanjing University of Science and Technology in China, with a research focus on the development of lithium/sodium ion batteries.

Jiaxuan Zou

Jiaxuan Zou graduated with a master’s degree from Nanjing University of Science and Technology in China, with a research focus on the development of positive electrode materials for sodium ion batteries.

Qiao Wu

Qiao Wu graduated with a master’s degree from Nanjing University of Science and Technology in China, with a research focus on the development of negative electrode materials for sodium ion batteries.

Wenju Wang

Wenju Wang is a professor and doctoral supervisor at Nanjing University of Science and Technology in China, with research interests in the development of lithium/sodium ion batteries and the application of new energy technologies.

Shaoliang Meng

Shaoliang Meng is a lecturer at Nanjing University of Science and Technology in China, specializing in the development and utilization of sodium ion batteries.

Yuqian Li

Yuqian Li is a lecturer at Nanjing University of Science and Technology in China, with a doctoral degree from Zhejiang University. His research focuses on the development of sodium ion batteries and the application of new energy technologies.

Xianzhong Tan

Xianzhong Tan, with a master’s degree, is currently a senior experimenter at the School of Energy at Nanjing University of Science and Technology in China.