Title: Vertical Co₉S₈ hollow nanowall arrays grown on a Celgard separator as a multifunctional polysulfide barrier for high-performance Li–S batteries

Abstract

Lithium–sulfur (Li–S) batteries have been regarded as one of the most promising next-generation energy-storage devices, due to their low cost and high theoretical energy density (2600 W h kg^-1). However, the severe dissolution of lithium polysulfides (LiPSs) and the fatal shuttle effect of the sulfur cathode seriously hinder the practical applications of Li–S batteries. To address such issues, we present here, for the first time, a novel metal organic framework (MOF)-derived Co₉S₈ nanowall array with vertical hollow nanoarchitecture and high electrical conductivity, which is grown in situ on a Celgard separator (Co₉S₈–Celgard) via a feasible and scalable liquid-reaction approach, as an efficient barrier for LiPSs in Li–S batteries. Benefiting from the direct in situ growth of vertical Co₉S₈ hollow nanowall arrays as a multifunctional polar barrier, the Co₉S₈–Celgard separator possesses large surface area, excellent mechanical stability, and particularly strong LiPS-trapping ability via chemical and physical interactions. With these advantages, even with a pure sulfur cathode with a high sulfur loading of 5.6 mg cm^-2, the Li–S cells with the Co₉S₈–Celgard separator exhibit outstanding electrochemical performance: the initial specific capacity is as high as 1385 mA h g^-1 with a retention of 1190 mA h g^-1 after 200 cycles. The cellsmore » deliver a high capacity of 530 mA h g^-1 at a 1C rate (1675 mA g^-1) even after an impressive number of 1000 cycles with an average capacity fade of only 0.039% per cycle, which is promising for long-term cycling application at high charge/discharge current densities, and pouch-type Li–S cells with the Co₉S₈–Celgard separator display excellent cycling performance. When the optimized cathode with the sulfur loading in well-designed yolk–shelled carbon@Fe₃O₄ (YSC@Fe₃O₄) nanoboxes is employed, the cell with Co₉S₈–Celgard delivers a high initial capacity of 986 mA h g^-1 at a 1C rate with a capacity retention as high as 83.2% even after a remarkable number of 1500 cycles. In conclusion, this work presents a strategy to grow on the separator a multifunctional polar interlayer with unique nanoarchitecture and high conductivity to chemically and physically trap the LiPSs, thus significantly enhancing the performance of Li–S batteries.« less

Authors:

He, Jiarui ^[1]; Chen, Yuanfu  ^[2];

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• Search DOE PAGES for ORCID "0000-0002-5521-6330"

Manthiram, Arumugam  ^[3]

• Search DOE PAGES for author "Manthiram, Arumugam"
• Search DOE PAGES for ORCID "0000-0003-0237-9563"

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+ Show Author Affiliations

1. Univ. of Texas, Austin, TX (United States). Materials Science and Engineering Program & Texas Materials Inst.; Univ. of Electronic Science and Technology of China, Chengdu (China)
2. Univ. of Electronic Science and Technology of China, Chengdu (China)
3. Univ. of Texas, Austin, TX (United States). Materials Science and Engineering Program & Texas Materials Inst.

Publication Date:

Tue Jun 19 00:00:00 EDT 2018

Research Org.:

Univ. of Texas, Austin, TX (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; China Scholarship Council

OSTI Identifier:

1598185

Alternate Identifier(s):

OSTI ID: 1457805

Grant/Contract Number:  

SC0005397; 201606070032

Resource Type:

Accepted Manuscript

Journal Name:

Energy & Environmental Science

Additional Journal Information:

Journal Volume: 11; Journal Issue: 9; Journal ID: ISSN 1754-5692

Publisher:

Royal Society of Chemistry

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; 25 ENERGY STORAGE