title: Truncated tetrahedron seed crystals initiating stereoaligned growth of FeSi nanowires.
abstract: We have synthesized epitaxially grown freestanding FeSi nanowires (NWs) on an m-Al(2)O(3) substrate by using a catalyst-free chemical vapor transport method. FeSi NW growth is initiated from FeSi nanocrystals, formed on a substrate in a characteristic shape with a specific orientation. Cross-section TEM analysis of seed crystals reveals the crystallographic structure and hidden geometry of the seeds. Close correlation of geometrical shapes and orientations of the observed nanocrystals with those of as-grown NWs indicates that directional growth of NWs is initiated from the epitaxially formed seed crystals. The diameter of NWs can be controlled by adjusting the composition of Si in a Si/C mixture. The epitaxial growth method for FeSi NWs via seed crystals could be employed to heteroepitaxial growth of other compound NWs.
authors.affiliation: Department of Chemistry, KAIST, Daejeon 305-701, Korea.
authors.forename: Si-in
authors.initials: SI
authors.lastname: Kim
authors.forename: Hana
authors.initials: H
authors.lastname: Yoon
authors.forename: Kwanyong
authors.initials: K
authors.lastname: Seo
authors.forename: Youngdong
authors.initials: Y
authors.lastname: Yoo
authors.forename: Sungyul
authors.initials: S
authors.lastname: Lee
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim
mesh_terms: D000497:Alloys / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D007501:Iron / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000497:Alloys; D046911:Macromolecular Substances; D007501:Iron; D012825:Silicon