title: Beads-Milling of Waste Si Sawdust into High-Performance Nanoflakes for Lithium-Ion Batteries.
abstract: Nowadays, ca. 176,640 tons/year of silicon (Si) (>4N) is manufactured for Si wafers used for semiconductor industry. The production of the highly pure Si wafers inevitably includes very high-temperature steps at 1400-2000 °C, which is energy-consuming and environmentally unfriendly. Inefficiently, ca. 45-55% of such costly Si is lost simply as sawdust in the cutting process. In this work, we develop a cost-effective way to recycle Si sawdust as a high-performance anode material for lithium-ion batteries. By a beads-milling process, nanoflakes with extremely small thickness (15-17 nm) and large diameter (0.2-1 μm) are obtained. The nanoflake framework is transformed into a high-performance porous structure, named wrinkled structure, through a self-organization induced by lithiation/delithiation cycling. Under capacity restriction up to 1200 mAh g-1, the best sample can retain the constant capacity over 800 cycles with a reasonably high coulombic efficiency (98-99.8%).
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Kasukabe
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.|PRESTO, The Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi 332-0012, Japan.
authors.forename: Hirotomo
authors.initials: H
authors.lastname: Nishihara
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Kimura
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Matsumoto
authors.affiliation: The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: Hikaru
authors.initials: H
authors.lastname: Kobayashi
authors.affiliation: Center for Technology Innovation-Materials, Hitachi Ltd., Hitachi, Ibaraki 319-1292, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Okai
authors.affiliation: Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kyotani