Higher manganese silicide nanowires of Nowotny chimney ladder phase.
We report the synthesis, structural identification, and electrical properties of the first one-dimensional (1-D) nanomaterials of a semiconducting higher manganese silicide (MnSi(2-x)) with widths down to 10 nm via chemical vapor deposition of the single-source precursor Mn(CO)(5)SiCl(3). The complex Nowotny chimney ladder structure of these homologous higher manganese silicides, also referred to as Mn(n)Si(2n-m), MnSi(1.75), or MnSi(1.8), contributes to the excellent thermoelectric performance of the bulk materials, which would be enhanced by phonon scattering due to 1-D nanoscale geometry. The morphology, structure, and composition of MnSi(2-x) nanowires and nanoribbons are examined using electron microscopy and X-ray spectroscopy. Elaborate select area electron diffraction analysis on single-crystal nanowires reveals the phase to be Mn(19)Si(33), one of a series of crystallographically distinct higher manganese silicides that have a Nowotny chimney ladder structure. Electrical transport study of single nanowires shows that they are degenerately doped with a low resistivity (17 mohms x cm) similar to the bulk.
Higgins
Jeremy M
JM
Department of Chemistry, University of Wisconsin-Madison,1101 University Avenue, Madison, Wisconsin 53706, USA.
Schmitt
Andrew L
AL
Guzei
Ilia A
IA
Jin
Song
S
D018360:Crystallography, X-Ray; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D053770:Nanowires / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*
D017655:Silicon Compounds; C539637:manganese silicide; D008345:Manganese