title: 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.
authors.affiliation: Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, USA.
authors.forename: Wei
authors.initials: W
authors.lastname: Luo
authors.forename: Xingfeng
authors.initials: X
authors.lastname: Wang
authors.forename: Colin
authors.initials: C
authors.lastname: Meyers
authors.forename: Nick
authors.initials: N
authors.lastname: Wannenmacher
authors.forename: Weekit
authors.initials: W
authors.lastname: Sirisaksoontorn
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lerner
authors.forename: Xiulei
authors.initials: X
authors.lastname: Ji
mesh_terms: D060326:Chemistry Techniques, Synthetic; D005857:Germanium / Q000737:chemistry*; D006358:Hot Temperature; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D005857:Germanium; C040516:germanium oxide; D012822:Silicon Dioxide; D012825:Silicon