Synthesis of Core-Shell Cu-Au Nanoparticles via a Redox-Transmetalation Method in Reverse Microemulsion

Core-shell Cu-Au nanoparticles were chemically synthesized through a redox-transmetalation method in reverse microemulsion. The powder X-ray diffraction patterns revealed the presence of crystalline gold and copper and the absence of any copper oxides or other byproducts. The core shell structure could be clearly observed by the transmission electron microscope (TEM). In addition, the Cu cores and the gold shells were further verified by the high-resolution transmission electron microscope (HRTEM). The diameter of the nanoparticles ranged from 15 to 25 nm, with 5-10 nm core diameters and 10-15 nm shell thickness. The UV-visible absorption spectra of these nanoparticles showed a red shift (relative to pure gold nanoparticles), also in agreement with the gold shell morphology.

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Coalescence between Au nanoparticles as induced by nanocurvature effect and electron beam athermal activation effect

Nanoscale ◽

10.1039/c7nr09710g ◽

2018 ◽

Vol 10 (17) ◽

pp. 7978-7983 ◽

Cited By ~ 1

Author(s):

Liang Cheng ◽

Xianfang Zhu ◽

Jiangbin Su

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Transmission Electron Microscope ◽

Room Temperature ◽

Electron Beam Irradiation ◽

Au Nanoparticles ◽

Beam Irradiation ◽

Activation Effect ◽

Transmission Electron

The coalescence of two single-crystalline Au nanoparticles on surface of amorphous SiOxnanowire, as induced by electron beam irradiation, wasin situstudied at room temperature in a transmission electron microscope.

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A simple method for the direct measurement of diffraction patterns in the EM400 T transmission electron microscope

Journal of Physics E Scientific Instruments ◽

10.1088/0022-3735/16/6/010 ◽

1983 ◽

Vol 16 (6) ◽

pp. 483-486 ◽

Cited By ~ 5

Author(s):

P Tambuyser

Keyword(s):

Electron Microscope ◽

Direct Measurement ◽

Transmission Electron Microscope ◽

Simple Method ◽

Transmission Electron ◽

Diffraction Patterns

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Crystalline to Amorphous Transformation of Fe3B By 1 MeV Electron Irradiation

MRS Proceedings ◽

10.1557/proc-7-203 ◽

1981 ◽

Vol 7 ◽

Cited By ~ 3

Author(s):

A. Mogro-Campero ◽

E.L. Hall ◽

J.L. Walter ◽

A.J. Ratkowski

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Electron Irradiation ◽

Room Temperature ◽

Ion Irradiation ◽

Rapid Quenching ◽

Al Alloy ◽

Bright Field ◽

Transmission Electron ◽

Diffraction Patterns

ABSTRACTSpecimens of amorphous Fe75B25 produced by rapid quenching from the melt were annealed to complete crystallization and subjected to 1 MeV electron irradiation in a transmission electron microscope at room temperature and at 130 K. The irradiation was interrupted at various intervals in order to obtain bright field images and diffraction patterns. The Fe3B crystals did not become amorphous at room temperature, even after damage levels of several dpa, whereas at 130 K the crystalline to amorphous transformation was observed to be complete at damage levels below 1 dpa. The results are combined with those of ion irradiation work on Fe3B; qualitative agreement is found between Fe3B and previous work on the Zr3Al alloy concerning their response to displacement damage by electron and ion irradiation.

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Diffraction patterns of artificial two-dimensional crystals synthesized in situ in an environmental scanning transmission electron microscope

Journal of Microscopy ◽

10.1111/j.1365-2818.2006.01555.x ◽

2006 ◽

Vol 221 (3) ◽

pp. 159-163

Author(s):

W. F. VAN DORP ◽

B. VAN SOMEREN ◽

C. W. HAGEN ◽

P. KRUIT ◽

P. A. CROZIER

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Scanning Transmission Electron Microscope ◽

Environmental Scanning ◽

Two Dimensional ◽

Scanning Transmission Electron ◽

Transmission Electron ◽

Scanning Transmission ◽

Diffraction Patterns

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Structure Transformations of the Decagonal and Icosahedral Phases in Quaternary Alloys.

MRS Proceedings ◽

10.1557/proc-235-551 ◽

1991 ◽

Vol 235 ◽

Author(s):

R. Perez ◽

J. Reyes-Gasga ◽

M. Jose-Yacaman

Keyword(s):

Electron Microscope ◽

Electron Diffraction ◽

Transmission Electron Microscope ◽

Icosahedral Phase ◽

Electron Radiation ◽

Quaternary Alloys ◽

Decagonal Phase ◽

Icosahedral Phases ◽

Transmission Electron ◽

Diffraction Patterns

ABSTRACTAn investigation of the phase transformations experienced by the decagonal and icosahedral phases in two different quaternary -alloys is carried out. The transformation in the decagonal phase of Al-Cu-Co-Si alloy is induced by the electron radiation in a transmission electron microscope. However, in the icosahedral phase of Al-Cu-Co-Fe alloy this transformation is induced by annealing. Electron diffraction patterns obtained from both phases suggest that the deformation mechanism involved in these kind of transitions is related with twinning

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In-situ Observations of Martensitic Transformation in Pure Ti Thin Films using the Dynamical Transmission Electron Microscope (DTEM)

MRS Proceedings ◽

10.1557/proc-0907-mm05-02 ◽

2005 ◽

Vol 907 ◽

Cited By ~ 1

Author(s):

Thomas Bradley LaGrange ◽

Geoffrey H. Campbell ◽

Jeffrey D. Colvin ◽

Wayne E. King ◽

Nigel D. Browning ◽

...

Keyword(s):

Electron Microscope ◽

Martensitic Transformation ◽

Electron Diffraction ◽

Transmission Electron Microscope ◽

Diffusion Mechanism ◽

Single Shot ◽

Transmission Electron ◽

Texture Modification ◽

Diffraction Patterns ◽

Ti Films

AbstractWe have measured the transient events of the α-β martensitic transformation in nanocrystalline Ti films via single shot electron diffraction patterns with 1.5 ns temporal resolution. This was accomplished with a newly constructed dynamic transmission electron microscope (DTEM), which combines pulsed laser systems and pump-probe techniques with a conventional TEM. The DTEM thereby enables studies of transformations that are (1) far too fast to be captured by conventional bulk techniques, and (2) difficult to study with current ultrafast electron diffraction (UED) instruments (which typically require an accumulation of multiple shots for each diffraction pattern). Martensitic transformations in nanocrystalline materials meet both criteria, with their rapid nucleation, characteristic interface velocities ∼1 km/s, and significant irreversible microstructural changes. Free-standing 40-nm-thick Ti films were laser-heated at a rate of ∼1010 K/s to a temperature above the 1155 K transition point, then probed at various time intervals with a 1.5-ns-long intense electron pulse. Diffraction patterns show an almost complete transition to the β phase within 500 ns. Post-mortem analysis (after the sample is allowed to cool) shows a reversion to the α phase coupled with substantial grain growth, lath formation, and texture modification. The cooled material also shows a complete lack of apparent dislocations, suggesting the possible importance of a "massive" short-range diffusion mechanism.

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Preparation of CuO-Decorated Core-Shell Montmorillonite-TiO2 Colloids and their Photocatalytic Activity for Hydrogen Evolution from Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.724-725.740 ◽

2013 ◽

Vol 724-725 ◽

pp. 740-743

Author(s):

Shi Zhao Kang ◽

Tan Wu ◽

Xiang Qing Li ◽

Qi Fan Wang ◽

Jin Mu

Keyword(s):

Photocatalytic Activity ◽

Electron Microscope ◽

Diffraction Analysis ◽

Hydrogen Evolution ◽

Uv Irradiation ◽

Transmission Electron Microscope ◽

Core Shell ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

CuO-decorated core-shell montmorillonite-TiO2 colloids were prepared and characterized with transmission electron microscope, powder X-ray diffraction analysis, Brunauer-Emmett-Teller analysis and UV-vis spectrua. Meanwhile, their photocatalytic activity for hydrogen evolution from water was explored under UV irradiation using methanol as a sacrificial reagent. The results indicate that they are an efficient photocatalyst with a rate of H2 evolution of 219 μmol·h-1·g-1 which is higher than that of anatase TiO2 nanoparticles.

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Investigations of Fine Grained Metallic Materials by Means of Orientation Maps in Transmission Electron Microscope

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.186.53 ◽

2012 ◽

Vol 186 ◽

pp. 53-57 ◽

Cited By ~ 3

Author(s):

Magdalena Bieda

Keyword(s):

Electron Microscope ◽

Transmission Electron Microscope ◽

Quantitative Description ◽

Ccd Camera ◽

Microscopic Investigation ◽

Automated System ◽

Fine Grained ◽

Transmission Electron ◽

Orientation Maps ◽

Diffraction Patterns

New subdivision of microscopic investigation called Orientation Microscopy (OM) is already well known in scanning electron microscope (SEM). Needs for investigation in nanoscale contribute to development of an appropriate method for transmission electron microscope (TEM). Automated acquisition and indexing of diffraction patterns, necessary for creation of orientation maps in TEM, cause more difficulties then in SEM. Nevertheless, the techniques of OM are also being developed in the Transmission Electron Microscope (TEM). Microdiffraction has been successfully introduced for creating such maps. Individual orientation measurements, which appeared in the convergent beam mode, can be used for quantitative description of microstructure of fine grained and deformed materials. The idea of the operation of the automated system in transmission electron microscope (TEM) which is developed in IMIM PAS relies on an automatic (with control position of the beam) acquisition of diffraction patterns using digital CCD camera, and indexing them, and then on the analysis of the set of individual crystallographic orientations. The graphic presentation of received sets of orientation can be analysed in order to obtain parameters and characteristics such as texture characteristics, characteristics of grain boundaries (based on orientation relationship) or the stereological characteristics. To illustrate application of this system, orientation maps measured in cold-rolled polycrystalline aluminium and its alloy 6013, and in multi-phase alloys of Fe-Cr-Co system after severe plastic deformation are presented.

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