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Cho, Kwon-Koo;Ha, Jong-Keun;Kim, Ki-Won;Ryu, Kwang-Sun;Kim, Hye-Sung
- Bulletin of the Korean Chemical Society
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- v.32 no.12
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- pp.4371-4376
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- 2011
In this work, we investigate the growth behavior of silicon oxide nanowires via a solid-liquid-solid process. Silicon oxide nanowires were synthesized at $1000^{\circ}C$ in an Ar and $H_2$ mixed gas. A pre-oxidized silicon wafer and a nickel film are used as the substrate and catalyst, respectively. We propose two distinctive growth modes for the silicon oxide nanowires that both act as a unique solid-liquid-solid growth process. We named the two growth mechanisms "grounded-growth" and "branched-growth" modes to characterize their unique solid-liquid-solid growth behavior. The two growth modes were classified by the generation site of the nanowires. The grounded-growth mode in which the grown nanowires are generated from the substrate and the branchedgrowth mode where the nanowires are grown from the side of the previously grown nanowires or at the metal catalyst drop attached at the tip of the nanowire stem.
https://doi.org/10.5012/bkcs.2011.32.12.4371 인용 PDF KSCI

Park, Deok-Yong;Chang, Chong-Hyun;Oh, Yong-Jun;Myung, Nosang V.;Yoo, Bongyoung
- Journal of the Korean institute of surface engineering
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- v.55 no.3
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- pp.143-155
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- 2022
Ceramic oxide layers successfully were formed on the surface of cast Al alloys with high Si contents using plasma electrolytic oxidation (PEO) process in electrolytes containing Na₂SiO₃, NaOH, and additives. The microstructure of the oxide layers was systematically analyzed using scanning electron microscopy (SEM), cross-sectional transmission electron microscopy (TEM), X-ray diffraction patterns (XRD), and energy X-ray dispersive spectroscopy (EDS). XRD analysis indicated that the PEO untreated high-silicon Al alloys (i.e., 17.1 and 11.7 wt.% Si) consist of Al, Si and Al₂Cu phases whereas Al₂Cu phase selectively disappeared after PEO treatment. PEO process yielded an amorphous oxide layer with few second phases including γ-Al₂O₃ and Fe-rich phases. The corrosion behaviors of high-silicon Al alloys treated by PEO process were investigated using electrochemical impedance spectroscopy (EIS) and other electrochemical techniques (i.e., open circuit potential and polarization curve). Electroanalytical studies indicated that high-silicon Al alloys treated by PEO process have greater corrosion resistance than high-silicon alloys untreated by PEO process.
https://doi.org/10.5695/JSSE.2022.55.3.143 인용 PDF KSCI