WO3 Nanostructures Synthesized by a Sonochemical Strategy

2009 ◽  
Vol 60-61 ◽  
pp. 16-21 ◽  
Author(s):  
Shi Bin Sun ◽  
Zeng Da Zou ◽  
Guang Hui Min
Keyword(s):  
Electron Microscopy ◽  
Tungsten Trioxide ◽  
Selective Adsorption ◽  
Morphological Evolution ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
Tungsten Hexachloride ◽  
Solvent Molecules ◽  
Transition Electron

A simple sonochemical synthesis of tungsten trioxide hydrate with various morphologies has been developed by using tungsten hexachloride (WCl6) as precursor and water, ethanol and their mixture as solvent, followed by annealing in a tube furnace. The resulting products were structurally characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transition electron microscopy (TEM) and differential thermal analysis (DTA). Results show that nanowhiskers emanating from the core of nanoparticles have been obtained with ethanol as solvent, and that nanoplates and nanosheets were formed when water and/or mixed ethanol and water was used as the solvent, respectively. The continuous changing supersaturation of tungsten trioxide may account for the formation of nanowhiskers. The formation of nanoplates or nanosheets may be associated with the selective adsorption of solvent molecules on the WO3 crystals. Due to a combination of the loss of chemical bonded water and crystal growth, the as-synthesized tungsten trioxide hydrate underwent apparent morphological evolution during thermal processing.

Strengthening of CP-Ti by Rolling at Room Temperature

2010 ◽  
Vol 667-669 ◽  
pp. 737-741
Author(s):  
Jian Hua Jiang ◽  
Yi Ding ◽  
Ai Dang Shan
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Mechanical Test ◽  
Commercial Purity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
Microstructure Observation ◽  
Cp Ti ◽  
Transition Electron

The effects of asymmetric and symmetric rolling at room temperature on mechanical properties and microstructure of the commercial purity Ti were investigated by means of mechanical test, optical microscopy, X-ray diffraction and transition electron microscopy. The results show that through asymmetric and symmetric rolling processes the ultimate tensile strength is substantially increased from 450 MPa to 960 MPa. Microstructure observation illustrates this variation in mechanical property is caused by the grain refinement and work hardening.

Structural and Chemical Characterization of Tungsten Gate Stack for 1 Gb Dram

2000 ◽  
Vol 611 ◽  
Author(s):  
O. Gluschenkov ◽  
J. Benedict ◽  
L.A. Clevenger ◽  
P. DeHaven ◽  
C. Dziobkowski ◽  
...  
Keyword(s):  
Side Wall ◽  
Chemical Characterization ◽  
X Ray Diffraction ◽  
Gate Stack ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
Tungsten Crystal ◽  
Material Interaction ◽  
Transition Electron

ABSTRACTMaterial interaction during integration of tungsten gate stack for 1 Gb DRAM was investigated by Transition Electron Microscopy (TEM), X-ray Diffraction analysis (XRD) and Auger Electron Spectroscopy (AES). During selective side-wall oxidation tungsten gate conductor undergoes a structural transformation. The transformation results in the reduction of tungsten crystal lattice spacing, re-crystallization of tungsten and/or growth of grains. During a highly selective oxidation process, a relatively small but noticeable amount of oxygen was incorporated into the tungsten layer. The incorporation of oxygen is attributed to the formation of a stable WO x (x<2) composite.

The Obtaining of Porous Strong Ceramics from Nano-Hydroxyapatite

2008 ◽  
Vol 3 (4) ◽  
pp. 40-46
Author(s):  
Dmitriy Yu. Trufanov ◽  
Andrey V. Nomoev ◽  
Molon D. Buyatuev ◽  
Dashima Zh. Bazarova ◽  
Deleg Sangaa ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Grain Size ◽  
Porous Ceramics ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
Gas Penetration ◽  
Transition Electron ◽  
Scanning Electron

The present paper describes the possibility of strong porous ceramics preparation from hydroxyapatite nanopowders. The as-dried hydroxyapatite nanopowders were uniaxially compacted and sintered. The sintered ceramics and nanopowders were analyzed by methods of transition electron microscopy, scanning electron microscopy and X-ray phase diffraction. The ceramics gas-penetration and hardness were measured. The methods of pore control were tested. The ceramics samples with open equally dispersed pores were received; the pores and grain size is about micron and less. The results are useful for making medical implantate and membrane ceramics with controlled pores size.

scholarly journals SYNTHESIS AND DIELECTRIC PROPERTIES OF NANOCRYSTALLINE BASRTIO3

2012 ◽  
Vol 05 ◽  
pp. 188-195
Author(s):  
M. Golmohammad ◽  
A. Nemati ◽  
M. A. Faghihi Sani
Keyword(s):  
Grain Size ◽  
Sol Gel ◽  
Simultaneous Thermal Analysis ◽  
Nanocrystalline Powders ◽  
Grain Size Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
Titanium Tetrabutoxide ◽  
Transition Electron

Ba 0.7 Sr 0.3 TiO 3 was prepared via simple sol-gel method by using titanium tetrabutoxide, barium and strontium carbonates, citric acid and ethylene glycol as starting materials. Simultaneous Thermal Analysis (STA) was used to examine thermal behavior of xerogel. The crystallite size of BST was about 21nm calculated by X-Ray diffraction (XRD) and confirmed by transition electron microscopy (TEM). Using these nanocrystalline powders, BST pellets were prepared and sintered in various temperatures. The grain size effect on electrical properties was studied and found that as the grain size decreased, the dielectric constant decreased too.

Polymorphological LaVO 4:Dy 3+ Phosphors: Hydrothermal Synthesis and Luminescent Properties

2011 ◽  
Vol 239-242 ◽  
pp. 1735-1738
Author(s):  
Guo Cong Liu ◽  
Ke Long Huang
Keyword(s):  
Electron Microscopy ◽  
Morphological Evolution ◽  
Hydrothermal Process ◽  
Luminescent Properties ◽  
Growth Mechanisms ◽  
X Ray Diffraction ◽  
Rod Bundles ◽  
X Ray ◽  
Rod Bundle ◽  
Scanning Electron

Tetragonal LaVO4:Dy3+ crystals with novel shapes of rod, rod-bundles and needle-like flower were successfully synthesized via a facile and surfactant-free hydrothermal process. The products were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoluminescence spectroscopy (PL).The experimental results showed that the concentration of the precursor and the reaction temperature played important roles in morphological evolution of LaVO4:Dy3+ crystals (NCs). It was found that needle-like flower LaVO4:Dy3+ exhibited the highest B/Y value compared with rod and rod-bundle samples. Possible growth mechanisms of polymorphological LaVO4:Dy3+ crystals were briefly discussed.

Synthesis and Characterization of Hierarchical Zeolite with High Mechanical Stability

2011 ◽  
Vol 217-218 ◽  
pp. 368-371 ◽  
Author(s):  
Xu Ling ◽  
Rui Liu Zong ◽  
Bin Kan Qiu
Keyword(s):  
Electron Microscopy ◽  
Self Assembly ◽  
Mechanical Stability ◽  
Three Dimensions ◽  
X Ray Diffraction ◽  
Polystyrene Spheres ◽  
Hierarchical Zeolite ◽  
Transition Electron Microscopy ◽  
Transition Electron

A hierarchical zeolite was synthesized by self-assembly of ZSM-5 nano-crystals colloid and polystyrene spheres coated with cationic poly (diallyldimethylammonium chloride). The colloidial ZSM-5 nano-crystals were first bound onto the polyelectrolyte-modified PS by electrostatic attraction, followed by centrifugation to form PS/ZSM-5 close-packed composite. After being dried and calcined to remove the organic components, the hierarchical zeolite was obtained. The X-ray diffraction, scanning electron microscopy, transition electron microscopy and N2 adsorp-tion-desorption techniques were employed to characterize the hierarchical zeolite. The results showed that the material prepared by this method was well crystallized and possessed uniform ma-cropores interconnected in three dimensions through windows. Furthermore, the hierarchical zeolite was rather mechanically stable.

scholarly journals The Effect of Zn and Zn–WO3 Composites Nano-Coatings Deposition on Hardness and Corrosion Resistance in Steel Substrate

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2253
Author(s):  
Channagiri Mohankumar Praveen Kumar ◽  
Manjunath Patel Gowdru Chandrashekarappa ◽  
Raviraj Mahabaleshwar Kulkarni ◽  
Danil Yurievich Pimenov ◽  
Khaled Giasin
Keyword(s):  
Electron Microscopy ◽  
Corrosion Resistance ◽  
Tungsten Trioxide ◽  
Steel Substrate ◽  
Composite Coatings ◽  
Nanocomposite Coatings ◽  
X Ray Diffraction ◽  
Electrodeposition Technique ◽  
X Ray ◽  
Scanning Electron

Pure Zn (Zinc) and its Zn–WO3 (Zinc–Tungsten trioxide) composite coatings were deposited on mild steel specimens by applying the electrodeposition technique. Zn–WO3 composites were prepared for the concentration of 0.5 and 1.0 g/L of particles. The influence of WO3 particles on Zn deposition, the surface morphology of composite, and texture co-efficient were analyzed using a variety of techniques, such as X-ray diffraction (XRD) and scanning electron microscopy (SEM) with Energy Dispersive X-ray analysis (EDX). Higher corrosion resistance and microhardness were observed on the Zn–WO3 composite (concentration of 1.0 g/L). The higher corrosion resistance and microhardness of 1.0 g/L Zn–WO3 nanocomposite coatings effectively protect the steel used for the manufacture of products, parts, or systems from chemical or electrochemical deterioration in industrial and marine ambient environments.

One-Step Hydrothermal Controlled Synthesis of HgTe Nanorods

2013 ◽  
Vol 303-306 ◽  
pp. 2667-2670
Author(s):  
Kun Peng Jiang ◽  
Li Jiang ◽  
Lei Liao ◽  
Wei Ping Yu ◽  
Ai Miao Qin ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Surface Roughness ◽  
Hydrothermal Synthesis ◽  
Controlled Synthesis ◽  
X Ray ◽  
Transition Electron Microscopy ◽  
One Step ◽  
Transition Electron ◽  
Scanning Electron

This paper describes a one-step hydrothermal synthesis of rod-shaped HgTe nanocrystals (NCs). X-ray powder diffraction (XRD), field scanning electron microscopy (FE-SEM), transition electron microscopy (TEM) and energy-dispersive X-ray analysis (EDX) have been used to characterize the HgTe NCs. The length, diameter, surface roughness and the aspect ratio of the HgTe nanorods are well controlled through Te precursor, reaction time and reductant.

scholarly journals Consolidation of Amorphous Powders by Hot Pressing

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
M. Tavoosi ◽  
F. Karimzadeh ◽  
M. H. Enayati ◽  
H. S. Kim
Keyword(s):  
Electron Microscopy ◽  
Hot Pressing ◽  
Intermetallic Phase ◽  
Average Crystallite Size ◽  
Bulk Sample ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Transition Electron Microscopy ◽  
Amorphous Powders ◽  
Transition Electron

The current study investigates the feasibility of fabricating amorphous Al80Fe10Ti5Ni5powders by mechanical alloying and consolidating them into bulk samples by a hot-pressing technique. As-milled and hot-pressed samples were examined by X-ray diffraction, scanning electron microscopy, transition electron microscopy, and differential scanning calorimetry. The results showed that milling of Al80Fe10Ti5Ni5powder for 40 h and hot pressing at 550°C under 600 MPa led to a fully dense bulk sample. During consolidation, an AlTi intermetallic phase with average crystallite size of 10 nm precipitates in the amorphous matrix.

CuO/polypyrrole nanocomposites as a marker of toxic lead ions for ecological remediation in contrast with CuO and polypyrrole

2015 ◽  
Vol 38 (5-6) ◽  
Author(s):  
Asha Radhakrishnan ◽  
Padmavathiamma Rejani ◽  
Bhaskaran Beena
Keyword(s):  
Electron Microscopy ◽  
Selective Adsorption ◽  
X Ray Diffraction ◽  
Order Model ◽  
X Ray ◽  
Adsorption Performance ◽  
Transmission Electron ◽  
Pseudo Second Order ◽  
Hazardous Metal ◽  
Ecological Remediation

AbstractIn the present study, CuO, polypyrrole (PPy), and CuO/PPy nanocomposites were synthesized to compare the selective adsorption behavior of hazardous metal ions such as Pb(II) ions. The synthesized nanomaterials were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer-Emmett-Teller surface area analysis, and energy dispersive X-ray spectroscopy. The adsorption studies clearly showed that CuO/PPy nanocomposites exhibited much higher adsorption performance than individual CuO and PPy. Kinetic data followed the pseudo-second-order model. The equilibrium attained at 120 min and isotherm follows the order Sips>Langmuir>Freundlich. The adsorbed Pb(II) is desorbed using 0.1

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