scholarly journals Газофазный синтез нового функционального гибридного материала на основе многостенных углеродных нанотрубок, декорированных ограненными нанокристаллами алюминия

2018 ◽  
Vol 44 (19) ◽  
pp. 24
Author(s):  
К.В. Кремлев ◽  
А.М. Объедков ◽  
Н.М. Семенов ◽  
Б.С. Каверин ◽  
С.Ю. Кетков ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Multiwalled Carbon ◽  
X Ray ◽  
Hybrid Nanomaterial ◽  
Transmission Electron ◽  
Aluminum Nanocrystals ◽  
First Time

AbstractThe deposition of polyhedral aluminum nanocrystals onto the surface of multiwalled carbon nanotubes (MWCNTs) via metalorganic chemical vapor deposition with the use of triisobutylaluminum as the precursor has been performed for the first time. The new hybrid nanomaterial (Al/MWCNTs) has been characterized by X-ray phase analysis, scanning electron microscopy, and high-resolution transmission electron microscopy. The obtained Al/MWCNTs hybrid materials were tested as the filler for the creation of threedimensional composites on the basis of an AMg2 alloy via powder metallurgy. It has been shown that the use of Al/MWCNTs as the filler increases the hardness of the composites by 18% in comparison with the initial MWCNTs.

Microstructures of GaN Films Grown on a LiGaO2 New Substrate by Metalorganic Chemical Vapor Deposition

1997 ◽  
Vol 468 ◽  
Author(s):  
Jing-Hong Li ◽  
Olga M. Kryliouk ◽  
Paul H. Holloway ◽  
Timothy J. Anderson ◽  
Kevin S. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Lattice Mismatch ◽  
Chemical Vapor ◽  
Threading Dislocations ◽  
Transmission Electron ◽  
Metalorganic Chemical

ABSTRACTMicrostructures of GaN films grown on the LiGaO2 by metalorganic chemical vapor deposition (MOCVD) have been characterized by transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). TEM and HRTEM results show that high quality single-crystal wurtzite GaN films have been deposited on the LiGaO2 and that the GaN film and the LiGaO2 have the following orientation relationship: (2110)(0002)GaN ̂ (002)LiGaO2 ^ 5–8°. A higher density of threading dislocations and stacking faults have been observed near the GáN/LiGaO2 interface, even though the lattice mismatch of GaN to LiGaO2 is only ∼1%. Threading dislocations with burgers vector b=<0001> and b=a/3<1120> are predominant in the GaN films. Also the GaN films contain some columnar inversion domain boundaries (IDBs). Both TEM and HRTEM results reveal that there is an unexpected amorphous or nano-crystalline inter-layer between the GaN and the LiGaO2 with a thickness of 50–100 nm.

A STUDY OF ALUMINA THIN FILMS GROWN BY LOW PRESSURE MOCVD: XPS AND AES

2002 ◽  
Vol 16 (08) ◽  
pp. 1261-1267 ◽  
Author(s):  
M. P. SINGH ◽  
S. A. SHIVASHANKAR ◽  
T. SHRIPATHI
Keyword(s):  
Vapor Deposition ◽  
Photoelectron Spectroscopy ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Alumina Film ◽  
Cross Sectional ◽  
X Ray ◽  
Transmission Electron ◽  
Low Pressure Mocvd ◽  
Substrate Temperatures

We have studied the chemical composition of alumina ( Al 2 O 3) films grown on Si(100) at different substrate temperatures by metalorganic chemical vapor deposition (MOCVD) using aluminium acetylactonate { Al(acac) 3} as the precursor. We have found that the resulting films of Al 2 O 3 contain substantial amounts of carbon. X-ray photoelectron spectroscopy (XPS) was employed to study the chemical state of carbon present in such films. The XPS spectrum reveals that the carbon present in Al 2 O 3 film is graphitic in nature. Auger electron spectroscopy (AES) was employed to study the distribution of carbon in the Al 2 O 3 films. The AES depth profile reveals that carbon is present throughout the film. The AES study on Al 2 O 3 films corroborates the XPS findings. An investigation of the Al 2 O 3/ Si (100) interface was carried out using cross-sectional transmission electron microscopy (XTEM). The TEM study reveals textured growth of alumina film on Si(100), with very fine grains of alumina embedded in an amorphous carbon-containing matrix.

Synthesis of Crystalline C3N4 films and the new C-N Phases

1996 ◽  
Vol 441 ◽  
Author(s):  
Yan Chen ◽  
D. J. Johnson ◽  
R. H. Prince ◽  
Liping Guo ◽  
E. G. Wang
Keyword(s):  
Electron Microscopy ◽  
Vapor Deposition ◽  
Growth Parameters ◽  
Chemical Vapor ◽  
Monoclinic Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lattice Constants ◽  
Transmission Electron ◽  
Hot Filament

AbstractCrystalline C-N films composed of α- and β-C3N4, as well as other C-N phases, have been synthesized via bias-assisted hot-filament chemical vapor deposition using a gas mixture of nitrogen and methane. Scanning electron microscopy(SEM), energy dispersive X-ray (EDX) analysis, X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the films. Lattice constants of the α- and β-C3N4 phases obtained coincide very well with the theoretical values. In addition to these phases, two new C-N phases in the films have been identified by TEM and XRD; one having a tetragonal structure with a = 5.65 Å, c = 2.75Å, and the second having a monoclinic structure with a = 5.065 Å, b= 11.5 Å, c = 2.801 Å and β = 96°. Their stoichiometric values and atomic arrangements have not yet been identified. Furthermore, variation in growth parameters, for example methane concentration, bias voltage, etc., can yield preferred growth of different C-N phases.

Synthesis and Cathodoluminescence of β-Ga2O3 Nanowires with Holes

2008 ◽  
Vol 8 (3) ◽  
pp. 1284-1287
Author(s):  
Xitian Zhang ◽  
Zhuang Liu ◽  
Suikong Hark
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Vapor Deposition ◽  
Gallium Oxide ◽  
Chemical Vapor ◽  
Oxide Nanowires ◽  
X Ray ◽  
Transmission Electron ◽  
Reactive Surfaces ◽  
Scanning Electron

Gallium oxide nanowires were synthesized on Si (001) substrate by chemical vapor deposition, using a Ga/Ga2O3 mixture as a precursor and Au as a catalyst. The structure of the as-synthesized products was examined by X-ray powder diffraction and high-resolution transmission electron microscopy, and found to be monoclinic β-Ga2O3. The morphologies of the β-Ga2O3 nanowires were characterized by scanning electron microscopy. The majority of the nanowires contain holes along their length, but a few were also found without holes. The holes are believed to be formed by the reaction of adsorbed Ga droplets on reactive terminating surfaces of the nanowires. For nanowires where these reactive surfaces are not exposed, the reaction of Ga is retarded. Cathodoluminescence (CL) of the nanowires was measured. Three emission bands centered at 376, 454, and 666 nm, respectively, were observed.

Compound growth and microstructure of carbon nanotube

2003 ◽  
Vol 18 (10) ◽  
pp. 2459-2463 ◽  
Author(s):  
Zaoli Zhang ◽  
Lian Ouyang ◽  
Zujin Shi ◽  
Zhennan Gu
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Carbon Nanotube ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Multiwalled Carbon ◽  
Catalyst Nanoparticles ◽  
Single Walled Carbon Nanotube ◽  
Fe Catalyst ◽  
Transmission Electron

The compound growth of single-walled carbon nanotube (SWCNT) and multiwalled carbon nanotube (MWCNT), which formed a nanotube cable, was achieved by the chemical vapor deposition of natural gas on an Fe catalyst supported on SiO2–Al2O3 hybrid materials at 950 °C. The microstructure of nanotubes was characterized by high-resolution transmission electron microscopy (HRTEM). The SWCNTs encapsulated inside MWCNTs can be two, three, or even more in quantity with a diameter range from 1.0 nm to 2.0 nm. The diameter of SWCNT is controlled by the size of the catalyst nanoparticles. Some bundles of SWCNT and double-walled nanotubes were also found. The possible mechanism of compound growth is briefly discussed.

Synthesis and Characterization of Exotic Carbon Fibers with Branched Spurs Using Nickel Catalyst Precursor

2013 ◽  
Vol 645 ◽  
pp. 3-9
Author(s):  
Qian Zhang ◽  
Qiu Xiang Wang ◽  
Hong Zhou Dong ◽  
Li Feng Dong
Keyword(s):  
Electron Microscopy ◽  
Nickel Catalyst ◽  
Carbon Fibers ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Chemical Vapor Deposition Method ◽  
Catalyst Precursor ◽  
X Ray ◽  
Transmission Electron

In this paper, we have synt hesized exotic carbon fibers with branched spurs by a chemical vapor deposition method using nickel catalyst precursor at 600 °C. No catalyst particles were found at the base of the carbon spurs, suggesting that the ni ckel catalyst particles, which were decomposed from the nickel catalyst precursor, facilitated the growth of the carbon fibers but not the spurs. The formation of the spurs resulted from the fluctuation of the carbon source gas acetylene flow. The samples were characterized by field emission sc anning electron microscopy, transmission electron microscopy, and X-ray powder diffraction.

Characteristics of Gallium Oxide Nanowires Synthesized by the Metalorganic Chemical Vapor Deposition

2007 ◽  
Vol 539-543 ◽  
pp. 1230-1235 ◽  
Author(s):  
Hyoun Woo Kim ◽  
S.H. Shim
Keyword(s):  
Chemical Vapor Deposition ◽  
Cross Sections ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Metalorganic Chemical

We have synthesized the high-density Ga2O3 nanowires on gold (Au)-coated silicon substrates using metalorganic chemical vapor deposition. The nanowires exhibited one-dimensional structures having circular cross sections with diameters in the range of 30-200 nm. The energy dispersive x-ray spectroscopy revealed that the nanowires contained elements of Ga and O, without Au-related impurities. X-ray diffraction analysis and high-resolution transmission electron microscopy showed that the Ga2O3 nanowires were crystalline.

Detection and Analysis of Phase Separation in Metalorganic Chemical Vapor Deposition InGaN

1997 ◽  
Vol 482 ◽  
Author(s):  
E. L. Piner ◽  
N. A. El-Masry ◽  
S. X. Liu ◽  
S. M. Bedair
Keyword(s):  
Chemical Vapor Deposition ◽  
Phase Separation ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Single Phase ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Metalorganic Chemical

AbstractInGaN films in the 0–50% InN composition range have been analyzed for the occurrence of phase separation. The ñ0.5 jum thick InGaN films were grown by metalorganic chemical vapor deposition (MOCVD) in the 690 to 780°C temperature range and analyzed by θ−20 x-ray diffraction (XRD), transmission electron microscopy (TEM), and selected area diffraction (SAD). As-grown films with up to 21% InN were single phase. However, for films with 28% InN and higher, the samples showed a spinodally decomposed microstructure as confirmed by TEM and extra spots in SAD patterns that corresponded to multiphase InGaN. An explanation of the data based on the GaN-InN pseudo-binary phase diagram is discussed.

SiGe Nanowires Grown by LPCVD: Morphological and Structural Analysis

2010 ◽  
Vol 1258 ◽  
Author(s):  
Andrés Rodríguez ◽  
Jesús Sangrador ◽  
Tomás Rodríguez ◽  
Carmen Ballesteros ◽  
Carmelo Prieto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Vapor Liquid Solid ◽  
Chemical Vapor Deposition Reactor ◽  
X Ray ◽  
Transmission Electron ◽  
Pressure Chemical ◽  
Scanning Electron

AbstractSiGe nanowires were grown by the vapor-liquid-solid method using a low pressure chemical vapor deposition reactor and different flows of the GeH4 and Si2H6 gas precursors. The morphology of the nanowires was studied by field emission scanning electron microscopy, and the length, diameter and density of nanowires were determined. Their structure and crystallinity were analyzed by transmission electron microscopy and its related techniques. Energy dispersive X-ray emission of individual nanowires as well a Raman spectroscopy were used to determine their composition and to analyze its homogeneity.

scholarly journals Metal film deposition by laser breakdown chemical vapor deposition

1986 ◽  
Vol 1 (3) ◽  
pp. 420-424 ◽  
Author(s):  
T.R. Jervis ◽  
L.R. Newkirk
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chemical Vapor Deposition ◽  
Gas Phase ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Film Deposition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Dielectric breakdown of gas mixtures can be used to deposit thin films by chemical vapor deposition with appropriate control of flow and pressure conditions to suppress gas-phase nucleation and particle formation. Using a pulsed CO2 laser operating at 10.6 μ where there is no significant resonant absorption in any of the source gases, homogeneous films from several gas-phase precursors have been sucessfully deposited by gas-phase laser pyrolysis. Nickel and molybdenum from the respective carbonyls representing decomposition chemistry and tungsten from the hexafluoride representing reduction chemistry have been demonstrated. In each case the gas precursor is buffered with argon to reduce the partial pressure of the reactants and to induce breakdown. Films have been characterized by Auger electron spectroscopy, x-ray diffraction, transmission electron microscopy, pull tests, and resistivity measurements. The highest quality films have resulted from the nickel depositions. Detailed x-ray diffraction analysis of these films yields a very small domain size consistent with the low temperature of the substrate and the formation of metastable nickel carbide. Transmission electron microscopy supports this analysis.

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