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Efficient fabrication of nanoporous si and Si/Ge enabled by a heat scavenger in magnesiothermic reactions.

ABSTRACT: Magnesiothermic reduction can directly convert SiO2 into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to convert diatom (SiO2) and SiO2/GeO2 into nanoporous Si and Si/Ge composite, respectively. Fusion of NaCl during the reaction consumes a large amount of heat that otherwise collapses the nano-porosity of products and agglomerates silicon domains into large crystals. Our methodology is potentially competitive for a practical production of nanoporous Si-based materials.

SUBMITTER: Luo W

PROVIDER: S-EPMC3713525 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Efficient fabrication of nanoporous si and Si/Ge enabled by a heat scavenger in magnesiothermic reactions.

Luo Wei W Wang Xingfeng X Meyers Colin C Wannenmacher Nick N Sirisaksoontorn Weekit W Lerner Michael M MM Ji Xiulei X

Scientific reports 20130101

Magnesiothermic reduction can directly convert SiO2 into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to convert diatom (SiO2) and SiO2/GeO2 into nanoporous Si and Si/Ge composite, respectively. Fusion of NaCl during the reaction consumes a large ...[more]

PMID: 23860418

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