title: Type I Clathrates as Novel Silicon Anodes: An Electrochemical and Structural Investigation.
abstract: Silicon clathrates contain cage-like structures that can encapsulate various guest atoms or molecules. An electrochemical evaluation of type I silicon clathrates based on Ba8AlySi46-yas the anode material for lithium-ion batteries is presented here. Postcycling characterization with nuclear magnetic resonance and X-ray diffraction shows no discernible structural or volume changes even after electrochemical insertion of 44 Li (≈1 Li/Si) into the clathrate structure. The observed properties are in stark contrast with lithiation of other silicon anodes, which become amorphous and suffer from large volume changes. The electrochemical reactions are proposed to occur as single phase reactions at approximately 0.2 and 0.4 V versus Li/Li+during lithiation and delithiation, respectively, distinct from diamond cubic or amorphous silicon anodes. Reversible capacities as high as 499 mAh g-1at a 5 mA g-1rate were observed for silicon clathrate with composition Ba8Al8.54Si37.46, corresponding to ≈1.18 Li/Si. These results show that silicon clathrates could be promising durable anodes for lithium-ion batteries.
authors.affiliation: Materials Science and Engineering School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Materials Science and Engineering School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA.
authors.forename: Rahul
authors.initials: R
authors.lastname: Raghavan
authors.affiliation: Materials Science and Engineering School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Wagner
authors.affiliation: Department of Chemistry and Biochemistry Arizona State University Tempe AZ 85287 USA.
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Davidowski
authors.affiliation: Materials Science and Technology Division Oak Ridge National Laboratory Oak Ridge TN 37831 USA.
authors.forename: Loïc
authors.initials: L
authors.lastname: Baggetto
authors.affiliation: Department of Chemistry and Biochemistry Arizona State University Tempe AZ 85287 USA.
authors.forename: Ran
authors.initials: R
authors.lastname: Zhao
authors.affiliation: Materials Science and Engineering School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA.
authors.forename: Qian
authors.initials: Q
authors.lastname: Cheng
authors.affiliation: Department of Chemistry and Biochemistry Arizona State University Tempe AZ 85287 USA.
authors.forename: Jeffery L
authors.initials: JL
authors.lastname: Yarger
authors.affiliation: Materials Science and Technology Division Oak Ridge National Laboratory Oak Ridge TN 37831 USA.
authors.forename: Gabriel M
authors.initials: GM
authors.lastname: Veith
authors.affiliation: Department of Materials Engineering Southwest Research Institute San Antonio TX 78238 USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Ellis-Terrell
authors.affiliation: Department of Materials Engineering Southwest Research Institute San Antonio TX 78238 USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Miller
authors.affiliation: Department of Materials Engineering Southwest Research Institute San Antonio TX 78238 USA.
authors.forename: Kwai S
authors.initials: KS
authors.lastname: Chan
authors.affiliation: Materials Science and Engineering School for Engineering of Matter Transport and Energy Arizona State University Tempe AZ 85287 USA.
authors.forename: Candace K
authors.initials: CK
authors.lastname: Chan
keywords: Li‐ion battery; anode; silicon; ternary type I clathrate