title: Discovery of abnormal lithium-storage sites in molybdenum dioxide electrodes.
abstract: Developing electrode materials with high-energy densities is important for the development of lithium-ion batteries. Here, we demonstrate a mesoporous molybdenum dioxide material with abnormal lithium-storage sites, which exhibits a discharge capacity of 1,814 mAh g(-1) for the first cycle, more than twice its theoretical value, and maintains its initial capacity after 50 cycles. Contrary to previous reports, we find that a mechanism for the high and reversible lithium-storage capacity of the mesoporous molybdenum dioxide electrode is not based on a conversion reaction. Insight into the electrochemical results, obtained by in situ X-ray absorption, scanning transmission electron microscopy analysis combined with electron energy loss spectroscopy and computational modelling indicates that the nanoscale pore engineering of this transition metal oxide enables an unexpected electrochemical mass storage reaction mechanism, and may provide a strategy for the design of cation storage materials for battery systems.
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.|Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Jeong Kuk
authors.initials: JK
authors.lastname: Shon
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.
authors.forename: Hyo Sug
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Republic of Korea.|Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Gwi Ok
authors.initials: GO
authors.lastname: Park
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Jeongbae
authors.initials: J
authors.lastname: Yoon
authors.affiliation: Department of Energy Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Eunjun
authors.initials: E
authors.lastname: Park
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.
authors.forename: Gyeong Su
authors.initials: GS
authors.lastname: Park
authors.affiliation: Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Soo Sung
authors.initials: SS
authors.lastname: Kong
authors.affiliation: Key Laboratory of Natural Resource of the Changbai Mountain and Functional Molecular (Yanbian University), Ministry of Education, Department of Chemistry, Park Road 977, Yanji City, Jilin Province 133002, China.
authors.forename: Mingshi
authors.initials: M
authors.lastname: Jin
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.
authors.forename: Jae-Man
authors.initials: JM
authors.lastname: Choi
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.
authors.forename: Hyuk
authors.initials: H
authors.lastname: Chang
authors.affiliation: Samsung Advanced Institute of Technology, Samsung Electronics Co., Ltd., Suwon 443-803, Republic of Korea.
authors.forename: Seokgwang
authors.initials: S
authors.lastname: Doo
authors.affiliation: Department of Chemistry, Sungkyunkwan University, Suwon 440-746, Republic of Korea.|Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Ji Man
authors.initials: JM
authors.lastname: Kim
authors.affiliation: Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Republic of Korea.
authors.forename: Won-Sub
authors.initials: WS
authors.lastname: Yoon
authors.affiliation: Fuel Cell Group, Corporate R&D Center, Samsung SDI Co., Ltd., Yongin 446-577, Republic of Korea.
authors.forename: Chanho
authors.initials: C
authors.lastname: Pak
authors.affiliation: Department of Energy Engineering, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Hansu
authors.initials: H
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
authors.forename: Galen D
authors.identifier: http://orcid.org/0000-0002-0837-5961
authors.initials: GD
authors.lastname: Stucky