title: Carbon-Coated, Diatomite-Derived Nanosilicon as a High Rate Capable Li-ion Battery Anode.
abstract: Silicon is produced in a variety of ways as an ultra-high capacity lithium-ion battery (LIB) anode material. The traditional carbothermic reduction process required is expensive and energy-intensive; in this work, we use an efficient magnesiothermic reduction to convert the silica-based frustules within diatomaceous earth (diatomite, DE) to nanosilicon (nanoSi) for use as LIB anodes. Polyacrylic acid (PAA) was used as a binder for the DE-based nanoSi anodes for the first time, being attributed for the high silicon utilization under high current densities (up to 4C). The resulting nanoSi exhibited a high BET specific surface area of 162.6 cm2g-1, compared to a value of 7.3 cm2g-1for the original DE. DE contains SiO2architectures that make ideal bio-derived templates for nanoscaled silicon. The DE-based nanoSi anodes exhibit good cyclability, with a specific discharge capacity of 1102.1 mAh g-1after 50 cycles at a C-rate of C/5 (0.7 A gSi-1) and high areal loading (2 mg cm-2). This work also demonstrates the fist rate capability testing for a DE-based Si anode; C-rates of C/30 - 4C were tested. At 4C (14.3 A gSi-1), the anode maintained a specific capacity of 654.3 mAh g-1- nearly 2x higher than graphite's theoretical value (372 mAh g-1).
authors.affiliation: Materials Science and Engineering Program, Department of Mechanical Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Brennan
authors.initials: B
authors.lastname: Campbell
authors.affiliation: Materials Science and Engineering Program, Department of Mechanical Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Robert
authors.initials: R
authors.lastname: Ionescu
authors.affiliation: Department of Chemistry, Department of Electrical and Computer Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Maxwell
authors.initials: M
authors.lastname: Tolchin
authors.affiliation: Department of Chemistry, Department of Electrical and Computer Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Kazi
authors.initials: K
authors.lastname: Ahmed
authors.affiliation: Materials Science and Engineering Program, Department of Mechanical Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Zachary
authors.initials: Z
authors.lastname: Favors
authors.affiliation: Materials Science and Engineering Program, Department of Mechanical Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Krassimir N
authors.initials: KN
authors.lastname: Bozhilov
authors.affiliation: Materials Science and Engineering Program, Department of Mechanical Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Cengiz S
authors.initials: CS
authors.lastname: Ozkan
authors.affiliation: Department of Chemistry, Department of Electrical and Computer Engineering, University of California, Riverside, Riverside, CA 92521 (USA).
authors.forename: Mihrimah
authors.initials: M
authors.lastname: Ozkan