Ultrathin dendrimer-graphene oxide composite film for stable cycling lithium-sulfur batteries.
Lithium-sulfur batteries (Li-S batteries) have attracted intense interest because of their high specific capacity and low cost, although they are still hindered by severe capacity loss upon cycling caused by the soluble lithium polysulfide intermediates. Although many structure innovations at the material and device levels have been explored for the ultimate goal of realizing long cycle life of Li-S batteries, it remains a major challenge to achieve stable cycling while avoiding energy and power density compromises caused by the introduction of significant dead weight/volume and increased electrochemical resistance. Here we introduce an ultrathin composite film consisting of naphthalimide-functionalized poly(amidoamine) dendrimers and graphene oxide nanosheets as a cycling stabilizer. Combining the dendrimer structure that can confine polysulfide intermediates chemically and physically together with the graphene oxide that renders the film robust and thin (<1% of the thickness of the active sulfur layer), the composite film is designed to enable stable cycling of sulfur cathodes without compromising the energy and power densities. Our sulfur electrodes coated with the composite film exhibit very good cycling stability, together with high sulfur content, large areal capacity, and improved power rate.
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Wen
W
Liu
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Jianbing
J
Jiang
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Ke R
KR
Yang
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.|College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Yingying
Y
Mi
Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06511.
Piranavan
P
Kumaravadivel
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Yiren
Y
Zhong
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Qi
Q
Fan
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Zhe
Z
Weng
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516.
Zishan
Z
Wu
Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06511.|Center for Research on Interface Structures and Phenomena, Yale University, New Haven, CT 06511.
Judy J
JJ
Cha
College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
Henghui
H
Zhou
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516; hailiang.wang@yale.edu victor.batista@yale.edu gary.brudvig@yale.edu.
Victor S
VS
Batista
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516; hailiang.wang@yale.edu victor.batista@yale.edu gary.brudvig@yale.edu.
Gary W
GW
Brudvig
Department of Chemistry and Energy Sciences Institute, Yale University, West Haven, CT 06516; hailiang.wang@yale.edu victor.batista@yale.edu gary.brudvig@yale.edu.
Hailiang
H
Wang
dendrimer; graphene oxide; lithium–sulfur battery; long cycle; ultrathin composite film