In Situ Self-Formed Nanosheet MoS3/Reduced Graphene Oxide Material Showing Superior Performance as a Lithium-Ion Battery Cathode

Uijin Chang; Jung Tae Lee; Jin-Mun Yun; Byeongyoung Lee; Seung Woo Lee; Han-Ik Joh; KwangSup Eom; Thomas F Fuller

doi:10.1021/acsnano.8b07191

In Situ Self-Formed Nanosheet MoS₃/Reduced Graphene Oxide Material Showing Superior Performance as a Lithium-Ion Battery Cathode

ACS Nano. 2019 Feb 26;13(2):1490-1498. doi: 10.1021/acsnano.8b07191. Epub 2018 Dec 27.

Authors

Uijin Chang¹, Jung Tae Lee², Jin-Mun Yun³, Byeongyoung Lee⁴, Seung Woo Lee⁴, Han-Ik Joh⁵, KwangSup Eom¹, Thomas F Fuller⁶

Affiliations

¹ School of Materials Science & Engineering , Gwangju Institute of Science and Technology (GIST) , 123 Cheomdangwagi-ro, Buk-gu , Gwangju , 61005 , Republic of Korea.
² Institute for Manufacturing, Department of Engineering , University of Cambridge , 17 Charles Babbage Road , Cambridge , CB3 0FS , United Kingdom.
³ Radiation Research Division for Industry and Environment , Korea Atomic Energy Research Institute (KAERI) , Geumgu-gil 29, Jeongeup-si , Jeollabuk-do 56212 , Republic of Korea.
⁴ George W. Woodruff School of Mechanical Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States.
⁵ Department of Energy Engineering , Konkuk University , 120 Neungdong-ro, Gwangjin-gu , Seoul 05029 , Republic of Korea.
⁶ School of Chemical & Biomolecular Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States.

PMID: 30580512
DOI: 10.1021/acsnano.8b07191

Abstract

Although lithium-sulfur (Li-S) batteries have 5-10 times higher theoretical capacity (1675 mAh g^-1) than present commercial lithium-ion batteries, Li-S batteries show a rapid and continuous capacity fading due to the polysulfide dissolution in common electrolytes. Here, we propose the use of a sulfur-based cathode material, amorphous MoS₃ and reduced graphene oxide (r-GO) composite, which can be substituted for the pure sulfur-based cathodes. In order to enhance kinetics and stability of the electrodes, we intentionally pulverize the microsized MoS₃ sheet into nanosheets and form an ultrathin nano-SEI on the surface using in situ electrochemical methods. Then, the pulverized nanosheets are securely anchored by the oxygen functional group of r-GO. As a result, the electrochemically treated MoS₃/r-GO electrode shows superior performance that surpasses pure sulfur-based electrodes; it exhibits a capacity of about 900 mAh g^-1 at a rate of 5C for 2500 cycles without capacity fading. Moreover, a full-cell battery employing the MoS₃/r-GO cathode with a silicon-carbon composite anode displays a 3-5 times higher energy density (1725 Wh kg^-1/7100 Wh L^-1) than present LIBs.

Keywords: in situ electrochemical treatment; lithium-ion battery cathode material; molybdenum trisulfide; nano solid electrolyte interphase layer; self-formed nanosheet.