Amorphous MoS 3 as the sulfur-equivalent cathode material for room-temperature Li–S and Na–S batteries

Ye, Hualin; Ma, Lu; Zhou, Yu; Wang, Lu; Han, Na; Zhao, Feipeng; Deng, Jun; Wu, Tianpin; Li, Yanguang; Lu, Jun

doi:10.1073/pnas.1711917114

Title: Amorphous MoS ₃ as the sulfur-equivalent cathode material for room-temperature Li–S and Na–S batteries

Journal Article · Mon Nov 27 00:00:00 EST 2017 · Proceedings of the National Academy of Sciences of the United States of America

DOI:https://doi.org/10.1073/pnas.1711917114· OSTI ID:1523292

Ye, Hualin ^[1]; Ma, Lu ^[2]; Zhou, Yu ^[1]; Wang, Lu ^[1]; Han, Na ^[1]; Zhao, Feipeng ^[1]; Deng, Jun ^[1]; Wu, Tianpin ^[2]; Li, Yanguang ^[1]; Lu, Jun ^[2]

Institute of Functional Nano and Soft Materials, Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou 215123, China,
Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439

Many problems associated with Li-S and Na-S batteries essentially root in the generation of their soluble polysulfide intermediates. While conventional wisdom mainly focuses on trapping polysulfides at the cathode using various functional materials, few strategies are available at present to fully resolve or circumvent this long-standing issue. In this study, we propose the concept of sulfur-equivalent cathode materials, and demonstrate the great potential of amorphous MoS₃ as such a material for room-temperature Li-S and Na-S batteries. In Li-S batteries, MoS₃ exhibits sulfur-like behavior with large reversible specific capacity, excellent cycle life, and the possibility to achieve high areal capacity. Most remarkably, it is also fully cyclable in the carbonate electrolyte under a relatively high temperature of 55 degrees C. MoS₃ can also be used as the cathode material of even more challenging Na-S batteries to enable decent capacity and good cycle life. Operando X-ray absorption spectroscopy (XAS) experiments are carried out to track the structural evolution of MoS₃. It largely preserves its chain-like structure during repetitive battery cycling without generating any free polysulfide intermediates.

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Research Organization:: Argonne National Lab. (ANL), Argonne, IL (United States)

Sponsoring Organization:: USDOE; Ministry of Science and Technology of the People's Republic of China; National Natural Science Foundation of China (NSFC); National Natural Science Foundation of Jiangsu Province; Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC); USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)

Grant/Contract Number:: AC02-06CH11357

OSTI ID:: 1523292

Alternate ID(s):: OSTI ID: 1461311

Journal Information:: Proceedings of the National Academy of Sciences of the United States of America, Journal Name: Proceedings of the National Academy of Sciences of the United States of America Vol. 114 Journal Issue: 50; ISSN 0027-8424

Publisher:: Proceedings of the National Academy of SciencesCopyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 138 works

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Title: Amorphous MoS 3 as the sulfur-equivalent cathode material for room-temperature Li–S and Na–S batteries

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Title: Amorphous MoS ₃ as the sulfur-equivalent cathode material for room-temperature Li–S and Na–S batteries