ChemInform Abstract: Carbothermal Synthesis of TiC Whiskers via a Vapor-Liquid-Solid Growth Mechanism.

AbstractCondensation experiments were performed in the simple but most fundamental system Mg-Si-O-H with forsterite vaporization source. At temperatures above about 1000°C, euhedral crystals of forsterite (Mg2SiO4) of a few μm were formed. These crystals are similar to olivines in Allende matrix. At temperatures below about 1000°C, whiskers of forsterite and enstatite (MgSiO3) were formed by vapor-liquid-solid growth mechanism. These whiskers are different from enstatite whiskers in interplanetary dust, which were probably formed at small super coolings.

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Carbothermal synthesis of TaC whiskers via a vapor-liquid-solid growth mechanism

Journal of Materials Research ◽

10.1557/jmr.1997.0320 ◽

1997 ◽

Vol 12 (9) ◽

pp. 2419-2427 ◽

Cited By ~ 25

Author(s):

M. Johnsson ◽

M. Nygren

Keyword(s):

Growth Mechanism ◽

Reduction Process ◽

Tantalum Carbide ◽

Ni Catalyst ◽

Particle Sizes ◽

Alkali Metal Chloride ◽

Vapor Liquid Solid ◽

Carbothermal Synthesis ◽

Vls Growth ◽

Vapor Liquid

Tantalum carbide whiskers have been synthesized via a vapor-liquid-solid (VLS) growth mechanism in the temperature region 1200–1300 °C in nitrogen or argon. The starting materials consisted of Ta2O5, C, Ni, and NaCl. Carbon was added to reduce tantalum pentoxide, via a carbothermal reduction process, and Ni was used to catalyze the whisker growth. Thermodynamic calculations showed that tantalum is transported in the vapor phase as an oxochloride rather than as a chloride. An alkali metal chloride such as NaCl can be used as a source of Cl. The formation of TaC whiskers was found to be strongly dependent on the processing conditions used, on the choice of precursor materials, e.g., their particle sizes, and on the mixing procedure. So far we have obtained TaC whisker in a yield of 75–90 vol %. These whiskers are 0.1–0.6 μm in diameter and 10–30 μm in length, and they are straight and exhibit smooth surfaces. The main impurities are TaC particles, minor amounts of unreacted carbon, and remnants of the Ni catalyst.

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Synthesis and characterization of carbon-poor SiC nanowires via vapor-liquid-solid growth mechanism

Ceramics International ◽

10.1016/j.ceramint.2018.12.131 ◽

2019 ◽

Vol 45 (5) ◽

pp. 6440-6446 ◽

Cited By ~ 6

Author(s):

ChuChu Guo ◽

Laifei Cheng ◽

Fang Ye ◽

Zhaochen Li ◽

Zeshui Xu

Keyword(s):

Growth Mechanism ◽

Synthesis And Characterization ◽

Vapor Liquid Solid ◽

Sic Nanowires ◽

Vapor Liquid Solid Growth ◽

Vapor Liquid

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The effect of Sn addition on GaAs nanowire grown by vapor–liquid–solid growth mechanism

Nanotechnology ◽

10.1088/1361-6528/aadedd ◽

2018 ◽

Vol 29 (46) ◽

pp. 465601 ◽

Cited By ~ 3

Author(s):

Han Gao ◽

Mykhaylo Lysevych ◽

Hark Hoe Tan ◽

Chennupati Jagadish ◽

Jin Zou

Keyword(s):

Growth Mechanism ◽

Vapor Liquid Solid ◽

Gaas Nanowire ◽

Vapor Liquid Solid Growth ◽

Vapor Liquid

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VLS Growth of Si nanowhiskers on a H-terminated Si{111} surface

MRS Proceedings ◽

10.1557/proc-536-305 ◽

1998 ◽

Vol 536 ◽

Cited By ~ 1

Author(s):

N. Ozaki ◽

Y. Ohno ◽

S. Takeda ◽

M. Hirata

Keyword(s):

High Pressure ◽

Growth Condition ◽

Growth Mechanism ◽

Quantum Confinement ◽

Critical Value ◽

Extended Defects ◽

Vapor Liquid Solid ◽

Minimum Diameter ◽

Vls Growth ◽

Vapor Liquid

AbstractWe have grown Si nanowhiskers on a Si{1111} surface via the vapor-liquid-solid (VLS) mechanism. The minimum diameter of the crystalline is 3nm and is close to the critical value for the effect of quantum confinement. We have found that many whiskers grow epitaxially or non-epitaxially on the substrate along the 〈112〉 direction as well as the 〈111〉 direction.In our growth procedure, we first deposited gold on a H-terminated Si{111} surface and prepared the molten catalysts of Au and Si at 500°C. Under the flow of high pressure silane gas, we have succeeded in producing the nanowhiskers without any extended defects. We present the details of the growth condition and discuss the growth mechanism of the nanowhiskers extending along the 〈112〉 direction.

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