Shape-Controlled Grown Au(Sn)-SnO2 Core-Shell Nanocables Via Vapor-Liquid-Solid (VLS) Growth Mechanism

2013 ◽  
Keyword(s):  
Growth Mechanism ◽  
Core Shell ◽  
Vapor Liquid Solid ◽  
Vls Growth ◽  
Shape Controlled ◽  
Vapor Liquid

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

1998 ◽  
Vol 536 ◽  
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.

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

1997 ◽  
Vol 12 (9) ◽  
pp. 2419-2427 ◽  
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.

Exploring SiC Growth Limitation of Vapor-Liquid-Solid Mechanism when Using Two Different Carbon Precursors

2013 ◽  
Vol 740-742 ◽  
pp. 323-326
Author(s):  
Kassem Alassaad ◽  
François Cauwet ◽  
Davy Carole ◽  
Véronique Soulière ◽  
Gabriel Ferro
Keyword(s):  
Growth Rate ◽  
High Growth ◽  
High Growth Rate ◽  
Carbon Precursor ◽  
Growth Limitation ◽  
Vapor Liquid Solid ◽  
Partial Pressures ◽  
Vapor Liquid Solid Mechanism ◽  
Vls Growth ◽  
Vapor Liquid

Abstract. In this paper, conditions for obtaining high growth rate during epitaxial growth of SiC by vapor-liquid-solid mechanism are investigated. The alloys studied were Ge-Si, Al-Si and Al-Ge-Si with various compositions. Temperature was varied between 1100 and 1300°C and the carbon precursor was either propane or methane. The variation of layers thickness was studied at low and high precursor partial pressure. It was found that growth rates obtained with both methane and propane are rather similar at low precursor partial pressures. However, when using Ge based melts, the use of high propane flux leads to the formation of a SiC crust on top of the liquid, which limits the growth by VLS. But when methane is used, even at extremely high flux (up to 100 sccm), no crust could be detected on top of the liquid while the deposit thickness was still rather small (between 1.12 μm and 1.30 μm). When using Al-Si alloys, no crust was also observed under 100 sccm methane but the thickness was as high as 11.5 µm after 30 min growth. It is proposed that the upper limitation of VLS growth rate depends mainly on C solubility of the liquid phase.

Vapor-liquid-solid Growth of III-Nitride Nanowires and Heterostructures by Metal-Organic Chemical Vapor Deposition

2004 ◽  
Vol 831 ◽  
Author(s):  
J. Su ◽  
M. Gherasimova ◽  
G. Cui ◽  
J. Han ◽  
S. Lim ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Mesoporous Molecular Sieves ◽  
Organic Chemical ◽  
Vapor Liquid Solid ◽  
Metal Organic ◽  
Vls Growth ◽  
Organic Chemical Vapor Deposition ◽  
Vapor Liquid

ABSTRACTWe report flexible synthesis of III-Nitride nanowires and heterostructures by metal-organic chemical vapor deposition (MOCVD) via a catalytic vapor-liquid-solid (VLS) growth mechanism. Indium is used as an in-situ catalyst to facilitate and sustain the stability of liquid phase droplet for VLS growth based on thermodynamic consideration. The employment of mesoporous molecular sieves (MCM-41) helps to prevent the coalescence of catalyst droplets and to promote nucleation statistics. Cathodoluminescence (CL) of GaN nanowires shows near band-edge emission at 370nm, and strong E2 phonon peak is observed at room temperature in Raman scattering spectra. Both binary GaN and AlN nanowires have been synthesized by MOCVD. Three-dimensional AlN/GaN trunk-branch nanostructures are reported to illustrate the versatility of incorporating the VLS mechanism into MOCVD process.

SHAPE EVOLUTION IN ONE-DIMENSIONAL ZnO NANOSTRUCTURES GROWN FROM ZnO NANOPOWDER SOURCE: VAPOR–LIQUID–SOLID VERSUS VAPOR–SOLID GROWTH MECHANISMS

2011 ◽  
Vol 10 (01n02) ◽  
pp. 75-79 ◽  
Author(s):  
SOUMEN DHARA ◽  
P. K. GIRI
Keyword(s):  
Growth Mechanism ◽  
Growth Temperature ◽  
Shape Evolution ◽  
Zno Nanostructures ◽  
Growth Mechanisms ◽  
Vapor Liquid Solid ◽  
One Dimensional ◽  
Zno Nanopowder ◽  
Simultaneous Growth ◽  
Vapor Liquid

Here we report on the growth and evolution of ZnO nanowires grown from ZnO nanopowder as a source material using a horizontal muffle furnace. The shape evolution has been studied with variation in growth temperature and zinc vapor pressure. The structural analysis on these nanostructures shows c-axis oriented aligned growth. Scanning electron microscopy imaging of these nanostructures revealed the shape evolution from nanowires to nanoribbons and then to nanorods as the growth temperature increases from 650°C to 870°C. At 650°C, only vertical nanowires have been observed and with increase in growth temperature nanowires transform to nanoribbons and then to nanorods at 870°C. And we also observed simultaneous growth of nanorods and nanoribbons under a specific growth condition. We believe that these nanowires and nanorods were formed by vapor–liquid–solid growth mechanism (catalyst-mediated growth), whereas nanoribbons were grown by vapor–solid growth mechanism (without the aid of a metal catalyst). We observed simultaneous occurrence of vapor–liquid–solid and vapor–solid growth mechanisms at a particular growth temperature. These ZnO nanowires exhibit bound exciton related UV emission at ~379 nm, and defect-emission band in the visible region. Possible growth mechanism, shape evolution, and simultaneous growth of two types of one-dimensional ZnO nanostructures under the same growth condition are discussed.

Shape-Controlled Synthesis of Single-Crystalline Nanopillar Arrays by Template-Assisted Vapor−Liquid−Solid Process

2010 ◽  
Vol 132 (40) ◽  
pp. 13972-13974 ◽  
Author(s):  
Onur Ergen ◽  
Daniel J. Ruebusch ◽  
Hui Fang ◽  
Asghar A. Rathore ◽  
Rehan Kapadia ◽  
...  
Keyword(s):  
Controlled Synthesis ◽  
Vapor Liquid Solid ◽  
Single Crystalline ◽  
Shape Controlled ◽  
Nanopillar Arrays ◽  
Vapor Liquid

Vapor-Liquid-Solid-Solid Growth Mechanism of Carbon Micro-coils

2006 ◽  
Vol 22 (06) ◽  
pp. 768-770
Author(s):  
LI Wen-Jun ◽  
◽  
◽  
XU Hai-Tao ◽  
GUO Yan-Chuan ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Vapor Liquid Solid ◽  
Vapor Liquid

scholarly journals Synthesis of Multiwall Boron Nitride (BN) Nanotubes by a PVD Method Based on Vapor–Liquid–Solid Growth

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 915 ◽  
Author(s):  
Hao Guo ◽  
Yonggang Xu ◽  
Hetuo Chen ◽  
Zhengjuan Wang ◽  
Xiaojian Mao ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Vapor Deposition ◽  
Physical Vapor Deposition ◽  
Liquid Drop ◽  
Synthesis Temperature ◽  
Vapor Liquid Solid ◽  
Vls Growth ◽  
Typical Length ◽  
Bn Nanotubes ◽  
Vapor Liquid

Multiwall boron nitride (BN) nanotubes were synthesized by a novel physical vapor deposition (PVD) method, in which the BN nanotubes grow on a compact substrate composed of AlN, γ-Al2O3, Y2O3, and carbon powders. The obtained BN nanotubes assemble in an orderly manner with a typical length of over one millimeter and a diameter of one-hundred nanometers. The hollow multiwall tubes have a spherical tip, which is presumed to be a liquid drop at the synthesis temperature, indicating the vapor–liquid–solid (VLS) growth mechanism.

Study on in-Situ Preparation and Growth Mechanism of TiCxN1-x Whiskers

2011 ◽  
Vol 197-198 ◽  
pp. 617-622
Author(s):  
Xue Wen Chong ◽  
Chuan Zhen Huang ◽  
Liang Xu ◽  
Bin Zou ◽  
Han Lian Liu ◽  
...  
Keyword(s):  
Growth Mechanism ◽  
Carbothermal Reduction ◽  
Reduction Process ◽  
Vapor Liquid Solid ◽  
Mixed Powder ◽  
Vapor Liquid Solid Mechanism ◽  
Vapor Liquid

TiCxN1-x whiskers were prepared using TiO2 and carbon mixed powder as the starting powder at the atmosphere of nitrogen by the carbothermal reduction process. NaCl and NiCl2 were added into the starting powder as the cosolvent and growth adds of impurities, respectively. An effect of the content of TiO2 and carbon in the starting powder on the TiCxN1-x whiskers was investigated. It is found from SEM and XRD observations that three types of TiCx N1-x whiskers are obtained when the different mol ratios of C and Ti are applied. The growth of whiskers is not only urged by the droplet on the top of whiskers, but also initiated by the helical dislocations. The growth of TiCxN1-x whiskers is controlled by the vapor-liquid-solid mechanism as well as vapor-solid mechanism.

Sign in / Sign up

Export Citation Format

Share Document