Ultra-thin nanosheets decorated in-situ S-doped 3D interconnected carbon network as interlayer modified Li-S batteries separator for accelerating adsorption-catalytic synergistic process of LiPSs

Wenjun Zhang; Xi Du; Maliang Zhang; Kunmei Su; Shulong Li; Zhenhuan Li

doi:10.1016/j.jcis.2024.02.202

Ultra-thin nanosheets decorated in-situ S-doped 3D interconnected carbon network as interlayer modified Li-S batteries separator for accelerating adsorption-catalytic synergistic process of LiPSs

J Colloid Interface Sci. 2024 Jun:663:735-748. doi: 10.1016/j.jcis.2024.02.202. Epub 2024 Feb 29.

Authors

Wenjun Zhang¹, Xi Du², Maliang Zhang¹, Kunmei Su³, Shulong Li⁴, Zhenhuan Li⁵

Affiliations

¹ State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin 300387, China; School of Materials Science and Engineering, Tianjin Key Laboratory of Advanced Fibers and Energy Storage, Tiangong University, Tianjin 300387, China.
² State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin 300387, China; School of Materials Science and Engineering, Tianjin Key Laboratory of Advanced Fibers and Energy Storage, Tiangong University, Tianjin 300387, China. Electronic address: duxi@tiangong.edu.cn.
³ State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin 300387, China; School of Chemistry and Chemical Engineering, Tiangong University, Tianjin 300387, China.
⁴ Institute for Advanced Study, Chengdu University, Chengdu 610106, China.
⁵ State Key Laboratory of Separation Membranes and Membrane Processes, Tiangong University, Tianjin 300387, China; School of Materials Science and Engineering, Tianjin Key Laboratory of Advanced Fibers and Energy Storage, Tiangong University, Tianjin 300387, China. Electronic address: lizhenhuan@tiangong.edu.cn.

PMID: 38432172
DOI: 10.1016/j.jcis.2024.02.202

Abstract

The shuttle effect of soluble lithium polysulfides (LiPSs) is primarily responsible for the unstable performance of lithium-sulfur (Li-S) batteries, which has severely impeded their continued development. In order to solve this problem, a special strategy is proposed. Specifically, ultra-thin NiCo based layered double hydroxides (named LDH or NiCo-LDH) nanosheets are implanted into a pre-designed 3D interconnected carbon networks (SPC) to obtain porous composite materials (named SPC-LDH).During the operation of the battery, the 3D interconnected porous carbon mesh was the first to rapidly adsorb LiPSs, and then the LDH on the surface of the carbon mesh was used to realize the catalytic conversion of LiPSs. This facilitates the electrochemical conversion reaction between S substances while addressing the "shuttle effect". As a result, the battery maintains a discharge capacity of 1401.9, 1114.3, 975.5, 880.7, 760.4 and 679.6 mAh g^-1 at the current densities of 0.1, 0.2, 0.5, 1, 2 and 3C, respectively. After 200 cycles at 2C, the battery's capacity stays at 732.9 mAh g^-1, meaning that the average rate of capacity decay is only 0.007 % per cycle. Moreover, in-situ XRD demonstrates the critical function of PP/SPC-LDH separators in inhibiting LiPSs and encouraging Li₂S transformation. The strong affinity of SPC-LDH for Li₂S₆ is also confirmed by density functional theory (DFT) calculation, offering more theoretical support for the synergistic adsorption process. This work offers a compelling method to develop modified separator materials that can counteract the "shuttle effect" in Li-S batteries.

Keywords: 3D interconnected structure; Blocking effect; Li-S battery separator; Synergy adsorption; Ultra-thin nanosheets.