Microstructures of the silicon carbide nanowires obtained by annealing the mechanically-alloyed amorphous powders

Journal Article · Wed Jul 15 04:00:00 EDT 2015 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2015.05.003· OSTI ID:22476113

Zhang, Pengfei; Li, Xinli

Silicon, graphite and boron nitride powders were mechanically alloyed for 40 h in argon. The as-milled powders were annealed at 1700 °C in nitrogen for 30 min. The annealed powders are covered by a thick layer of gray–green SiC nanowires, which are 300 nm to 1000 nm in diameter and several hundred microns in length. Trace iron in the raw powders acts as a catalyst, promoting the V–L–S process. It follows that the actual substances contributing to the growth of the SiC nanowires may be silicon, graphite and the metal impurities in the raw powders. The results from HRTEM and XRD reveal that the products contain both straight α/β-SiC nanowires and nodular α/β-SiC nanochains. It is interestingly found that 6H–SiC coexists with 3C–SiC in one nodular nanowire. This novel structure may introduce periodic potential field along the longitudinal direction of the nanowires, and may find applications in the highly integrated optoelectronic devices. - Graphical abstract: Display Omitted - Highlights: • SiC nanowires were prepared by annealing the mechanically alloyed amorphous powders. • SiC nanowires are 300 nm to 1000 nm in diameter and several hundred microns in length. • The products contain both straight α/β-SiC nanowires and nodular α/β-SiC nanochains. • Trace Fe in the raw powders acts as a catalyst, promoting the V–L–S process. • 6H–SiC coexists with 3C–SiC in one nodular SiC nanowire.

• OSTI ID: 22476113
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 105; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

77 NANOSCIENCE AND NANOTECHNOLOGY
ALLOYS
ANNEALING
BORON NITRIDES
CATALYSTS
GRAPHITE
IMPURITIES
IRON
LAYERS
MICROSTRUCTURE
NANOWIRES
NITROGEN
PERIODICITY
POWDERS
SILICON
SILICON CARBIDES
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION