Preparation and Characterization of Cu-SiO2 Nanoparticles

2007 ◽  
Vol 121-123 ◽  
pp. 255-258 ◽  
Author(s):  
Young Hwan Kim ◽  
Beong Gi Jo ◽  
Jee Hean Jeong ◽  
Young Soo Kang
Keyword(s):  
Silica Nanoparticles ◽  
Room Temperature ◽  
Sio2 Nanoparticles ◽  
Hybrid Structures ◽  
Cu Nanoparticles ◽  
Stöber Method ◽  
X Ray ◽  
Transmission Electron ◽  
Hydrolysis And Condensation

A room temperature route for doping silica particles with Cu nanoparticles to achieve hybrid structures is introduced. First, silica nanoparticles were synthesized according to the well-known Stöber method by hydrolysis and condensation of TEOS in a mixture of ethanol with water, using ammonia as catalyst to initiate the reaction. These SiO2 nanoaprticles were dried at 100 oC. We measured the size of these nanoparticles with transmission electron microscopy (TEM). Second, Cu-SiO2 nanoparticles were synthesized by reaction with CuCl2 and SiO2 nanoparticles in presence of catalyst at room temperature for 12 hrs. Results show silica nanoparticles of about 70 nm size with regularly deposited Cu nanoparticles. Cu-SiO2 nanoparticles were investigated with TEM images, energy dispersive X-ray analysis (EDX) spectrum and so on.

scholarly journals Characterization of Pd Impurities and Finite-Sized Defects in Detector Grade CdZnTe

2011 ◽  
Vol 1341 ◽  
Author(s):  
M.C. Duff ◽  
J.P. Bradley ◽  
Z.R. Dai ◽  
N. Teslich ◽  
A. Burger ◽  
...  
Keyword(s):  
Room Temperature ◽  
Cubic Phase ◽  
Secondary Phases ◽  
Detector Performance ◽  
X Ray ◽  
Metal Impurities ◽  
Transmission Electron ◽  
Large Numbers ◽  
Topographic Imaging

ABSTRACTSynthetic CdZnTe or “CZT” crystals are highly suitable for γ-spectrometers operating at the room temperature. Secondary phases (SP) in CZT are known to inhibit detector performance, particularly when they are present in large numbers or dimensions. These SP may exist as voids or composites of non-cubic phase metallic Te layers with bodies of polycrystalline and amorphous CZT material and voids. Defects associated with crystal twining may also influence detector performance in CZT. Using transmission electron microscopy, we identify two types of defects that are on the nano scale. The first defect consists of 40 nm diameter metallic Pd/Te bodies on the grain boundaries of Te-rich composites. Although the nano-Pd/Te bodies around these composites may be unique to the growth source of this CZT material, noble metal impurities like these may contribute to SP formation in CZT. The second defect type consists of atom-scale grain boundary dislocations. Specifically, these involve inclined “finite-sized” planar defects or interfaces between layers of atoms that are associated with twins. Finite-sized twins may be responsible for the subtle but observable striations that can be seen with optical birefringence imaging and synchrotron X-ray topographic imaging.

SYNTHESIS AND CHARACTERIZATION OF BIFUNCTIONAL CoFe2O4–ZnS NANOCOMPOSITE

2011 ◽  
Vol 10 (01n02) ◽  
pp. 237-240 ◽  
Author(s):  
J. P. BORAH ◽  
C. BORGOHAIN ◽  
K. C. SARMA ◽  
K. K. SENAPATI ◽  
P. PHUKAN
Keyword(s):  
Drug Targeting ◽  
Room Temperature ◽  
Cobalt Ferrite ◽  
Magnetic Nanomaterials ◽  
X Ray Diffraction ◽  
Chemical Route ◽  
Magnetic Fluid Hyperthermia ◽  
X Ray ◽  
Transmission Electron

The synthesis of composite magnetic nanomaterials has received increasing attention due to their electronic, magnetic, catalytic, and chemical or biological sensing properties. We have prepared cobalt ferrite–zinc sulfide nanocomposites by a chemical route. The synthesized nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), and photoluminescence spectrometer (PL). The fluorescent magnetic nanoparticles (FMNPs) had a typical diameter of 30±5 nm and saturation magnetization of 5.8 emu g-1 at room temperature. So, these FMNPs may be potentially applied in different fields such as optoelectronic devices, biolabeling, imaging, drug targeting, bioseparation, magnetic fluid hyperthermia, etc.

Solvothermal Synthesis and Characterization of Lithium Tantalate Nanoparticles

2014 ◽  
Vol 602-603 ◽  
pp. 19-22 ◽  
Author(s):  
Lin Qiang Gao ◽  
Hai Yan Chen ◽  
Zhen Wang ◽  
Xin Zou
Keyword(s):  
Electron Microscopy ◽  
Solvothermal Synthesis ◽  
Room Temperature ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Particle Size And Morphology ◽  
Size And Morphology

Nanoscale LiTaO3 powders with perovskite structure were synthesized using the solvothermal technique with glycol as solvent at 240°C for 12h. The powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). XRD was used to elucidate room temperature structures using Rietveld refinement. The powders were pure single pervoskite phase with high crystallinity. FESEM and TEM were used to determine particle size and morphology. The average LiTaO3 grain size was estimated to be < 200nm, and TEM images indicated that LiTaO3 particles had a brick-like morphology. In addition, the effect of the temperature on the LiTaO3 power characterisitics was also detailed studied.

Electrical Resistivity Improvement by Precipitation and Strain in Al-Cu Thin Films

2010 ◽  
Vol 305-306 ◽  
pp. 33-37 ◽  
Author(s):  
S. Lallouche ◽  
M.Y. Debili
Keyword(s):  
Thin Films ◽  
Copper Content ◽  
Room Temperature ◽  
Structural Features ◽  
X Ray Diffraction ◽  
X Ray ◽  
Glass Substrates ◽  
Transmission Electron ◽  
Hall Method

This work deals with Al-Cu thin films, deposited onto glass substrates by RF (13.56MHz) magnetron sputtering, and annealed at 773K. The film thickness was approximately the same 3-4µm. They are characterized with respect to microstructure, grain size, microstrain, dislocation density and resistivity versus copper content. Al (Cu) deposits containing 1.8, 7.21, 86.17 and 92.5at%Cu have been investigated. The use of X-ray diffraction analysis and transmission electron microscopy lead to the characterization of different structural features of films deposited at room temperature (< 400K) and after annealing (773K). The resistivity of the films was measured using the four-point probe method. The microstrain profile obtained from XRD thanks to the Williamson-Hall method shows an increase with increasing copper content.

Nanocrystalline and stacking-disordered β-cristobalite AlPO4 chemically stabilized at room temperature: synthesis, physical characterization, and X-ray powder diffraction data

2017 ◽  
Vol 32 (S1) ◽  
pp. S193-S200
Author(s):  
B. Peplinski ◽  
B. Adamczyk ◽  
P. Formanek ◽  
C. Meyer ◽  
O. Krüger ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Powder Diffraction ◽  
Title Compound ◽  
Room Temperature ◽  
Optical Emission ◽  
Xrd Pattern ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron

This paper reports the first successful synthesis and the structural characterization of nanocrystalline and stacking-disordered β-cristobalite AlPO4 that is chemically stabilized down to room temperature and free of crystalline impurity phases. Several batches of the title compound were synthesized and thoroughly characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectroscopy mapping in SEM, solid-state 31P nuclear magnetic resonance (31P-NMR) spectroscopy including the TRAPDOR method, differential thermal analysis (DTA), gas-sorption methods, optical emission spectroscopy, X-ray fluorescence spectroscopy, and ion chromatography. Parameters that are critical for the synthesis were identified and optimized. The synthesis procedure yields reproducible results and is well documented. A high-quality XRD pattern of the title compound is presented, which was collected with monochromatic copper radiation at room temperature in a wide 2θ range of 5°–100°.

Nanoemulsion Synthesis of Magnetic-Optical CoNiAu Nanoparticles

2014 ◽  
Vol 904 ◽  
pp. 90-94
Author(s):  
Hong Qin Shao ◽  
Zheng Guan ◽  
Jun Hua Wu ◽  
Hong Ling Liu
Keyword(s):  
Magnetic Properties ◽  
Biomedical Applications ◽  
Room Temperature ◽  
Vibrating Sample Magnetometry ◽  
Tem Analysis ◽  
X Ray ◽  
Near Ir ◽  
Transmission Electron ◽  
Optical And Magnetic Properties

Multi-functional CoNiAu nanoparticles were successfully synthesized via nanoemulsion method with the use of PEO-PPO-PEO as the surfactant, C14H29CH(OH)CH2OH as the reducing agent, Ni (acac)2, Co (acac)2 and Au (ac)3 as precursors. The characterization of the CoNiAu nanoparticles was performed using X-ray powder diffraction (XRD), fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and UV-vis near IR spectrophotometer (UV-vis). The XRD and TEM analysis confirm the formation and structure of the nanoparticles. The UV-vis and VSM measurements display the optical and magnetic properties of the CoNiAu nanoparticles at the room temperature. The CoNiAu nanoparticles with the well defined optical and magnetic properties are promised for optical, magnetic, catalytic and biomedical applications.

Preparation and Characterization of Gold-Loaded Magnetite/Silica Core-Shell Composites

2016 ◽  
Vol 42 ◽  
pp. 47-52
Author(s):  
Dan Dan Huang ◽  
Zhao Dai ◽  
Kun Yang ◽  
Yuan Yuan Chu
Keyword(s):  
Room Temperature ◽  
Solvothermal Reaction ◽  
Core Shell ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Core ◽  
Transmission Electron ◽  
Silica Core ◽  
Shell Particles

The fabrication of gold-loaded magnetite/silica core-shell particles was presented in this paper. First, 250 nm of magnetic Fe3O4 nanoparticles were prepared by solvothermal reaction. Then, the Fe3O4 particles were coated by SiO2, and Au nanoparticles (AuNPs), respectively. The core-shell structure of these microspheres was confirmed by transmission electron microscopy (TEM) and Power X-ray diffraction (XRD). The magnetic property of the core-shell microspheres was investigated at room temperature. The results indicated that the core-shell composites had a well-retained high magnetic intensity, thus it can be easily separated from the mixture in less than a few minutes by simply using a magnet.

scholarly journals Synthesis and Characterization of ZnTe Hierarchical Nanostructures

2012 ◽  
Vol 2012 ◽  
pp. 1-5
Author(s):  
Baohua Zhang ◽  
Fuqiang Guo ◽  
Wei Wang
Keyword(s):  
Photoluminescence Spectrum ◽  
Room Temperature ◽  
Thermal Evaporation ◽  
X Ray Diffraction ◽  
Green Luminescence ◽  
Hierarchical Nanostructures ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron Microcopy

Single-crystalline ZnTe hierarchical nanostructures have been successfully synthesized by a simple thermal evaporation technology. The as-prepared products were characterized with X-ray diffraction (XRD), scanning electron microcopy (SEM), transmission electron microscope (TEM), and photoluminescence spectrum (PL). These results showed that the ZnTe hierarchical nanostructures consisted of nanowires and nanolumps. The room temperature PL spectrum exhibited a pure green luminescence centered at 545nm. The growth mechanism of hierarchical nanostructure was also discussed.

Synthesis and Characterization of Spherical Hollow Assembly Composed of Cu Nanoparticles

2007 ◽  
Vol 72 (10) ◽  
pp. 1375-1382 ◽  
Author(s):  
Ming Yang ◽  
Xiao Yang
Keyword(s):  
Hollow Spheres ◽  
Decisive Role ◽  
Average Diameter ◽  
Synthesis And Characterization ◽  
Cu Nanoparticles ◽  
X Ray ◽  
Transmission Electron ◽  
Direct Attack ◽  
Spherical Hollow

Hollow spheres of Cu nanoparticles with an average diameter of 300-500 nm have been prepared by a simple reaction of CuCl and hydrazine in suspension in the presence of gelatin at 60 °C. Gelatin played a decisive role as an inhibitor of the direct attack of hydrazine on CuCl surfaces and in coagulation of the growing Cu producing the hollow spheres. The products were characterized by X-ray powder diffraction, transmission electron microscopy, UV-VIS absorption spectroscopy and X-ray photoelectron spectrometry.

Synthesis and Characterization of Strongly Fluorescent CdTe Nanocrystal Colloids

1999 ◽  
Vol 581 ◽  
Author(s):  
Frederic V. Mikulec ◽  
Moungi G. Bawendi
Keyword(s):  
Room Temperature ◽  
Deep Trap ◽  
Trioctylphosphine Oxide ◽  
Quantum Yields ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cdte Nanocrystals ◽  
Transmission Electron ◽  
Cdte Nanocrystal

ABSTRACTWe present a synthesis of colloidal CdTe nanocrystals whose absolute room temperature quantum yields are routinely above 60%. The preparation is based on the trioctylphosphine oxide (TOPO) method reported by Murray, with a more stalbe tellurium precursor now used as the chalcogenide source. The photoluminescence is continuously tunable over the range 590-760 nm and is as narrow as 135 meV (45 nm) FWHM. No deep trap luminescence is detected for the diameter range 4-11 nm. CdTe nanocrystals are characterized by UV/vis absorption, photoluminescence emission, transmission electron microscopy, and powder X-ray diffraction.

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