Investigation of polymer-protected noble metal nanoparticles by transmission electron microscopy: control of particle morphology and shape

1998 ◽  
Vol 276 (9) ◽  
pp. 769-779 ◽  
Author(s):  
A. Mayer ◽  
M. Antonietti
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Metal Nanoparticles ◽  
Noble Metal ◽  
Particle Morphology ◽  
Noble Metal Nanoparticles ◽  
Transmission Electron

Phosphotungstic acid staining of latexes for transmission electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 30-31
Author(s):  
O. L. Shaffer ◽  
M. S. El-Aasser ◽  
J. W. Vanderhoff
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Glass Transition ◽  
Phosphotungstic Acid ◽  
Particle Morphology ◽  
Ethyl Acrylate ◽  
Uranyl Acetate ◽  
Positive Staining ◽  
Sample Treatment ◽  
Transmission Electron

Measurement of particle size and particle morphology by transmission electron microscopy (TEM) is important in the characterization of polymer latex systems. Special sample treatment methods have been developed to permit the study of latexes that present problems, such as low-glass-transition-temperature (Tg) and electron-transparent particles. Some of these methods include hardening and staining by osmium tetroxide or bromine of latexes that contain unsaturation, negative staining by uranyl acetate, and freezing of latexes with low glass-transition temperatures.We have recently found phosphotungstic acid (PTA) to be useful in both negative and positive staining of latex particles. As a negative stain, PTA can enhance the contrast between the electron-transparent particles and the dense PTA-stained background. This has been particularly useful with latexes such as poly(butyl acrylate), poly(ethyl acrylate), poly(ethylene), and other polymers of similar electron densities. As a positive stain, PTA can also react with the surface functional groups of particles, such as hydroxyl, carboxyl, and amine groups.

scholarly journals One-step synthesis of gold and silver non-spherical nanoparticles mediated by Eosin Methylene Blue agar

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Diego Alberto Lomelí-Rosales ◽  
Adalberto Zamudio-Ojeda ◽  
Sara Angélica Cortes-Llamas ◽  
Gilberto Velázquez-Juárez
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Methylene Blue ◽  
Silver Nanoparticles ◽  
Metal Nanoparticles ◽  
Reduction Process ◽  
Gold And Silver Nanoparticles ◽  
Transmission Electron ◽  
One Step ◽  
Conventional Plate

AbstractNowadays, there are several approaches reported to accomplish the green synthesis of metal nanoparticles by using bacterial and fungi supernatants or by-products generated by these microorganisms. Therefore, agars as solely reductive regents have started to be used in order to obtain metal nanoparticles. This paper shows the results of the synthesis of gold and silver nanoparticles with different morphology, mainly triangular and truncated triangular, using Eosin Methylene Blue (EMB) agar as reducing agent. To control the reaction process, the necessary activation energy for the reducer was provided by three different techniques: microwave radiation, using a domestic microwave oven, ultraviolet radiation, and heating on a conventional plate. The evolution of the reduction process and stability of the samples was performed by ultraviolet visible spectroscopy. Morphology was carefully analyzed using high-resolution transmission electron microscopy (HRTEM) and Transmission electron microscopy (TEM). A one step synthesis for gold and silver nanoparticles was optimized with an eco-friendly and economic process.

Synthesis of Anatase-Based Titania Nanostructures Using Extreme Hydrothermal Conditions

2012 ◽  
Vol 463-464 ◽  
pp. 1493-1496
Author(s):  
Vorrada Loryuenyong ◽  
Pat Sooksaen ◽  
Phiphatphong Sanitchai
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Phase Transformation ◽  
Anatase Phase ◽  
Particle Morphology ◽  
Hydrothermal Conditions ◽  
X Ray ◽  
Calcination Temperatures ◽  
Transmission Electron ◽  
Titania Nanostructures

TiO2nanostructures with a pure anatase phase were successfully synthesized using hydrothermal treatment of P25-TiO2nanoparticles. These nanostructures were characterized using transmission electron microscopy (TEM) and x-ray powder diffraction measurements. The dependences of reaction temperature and calcination temperature on titanate-anatase phase transformation and the morphology of TiO2nanostructures were also discussed. The results demonstrated that phase composition and particle morphology can be controlled by both the reaction and calcination temperatures.

scholarly journals Comparative Study on the Influence of Noble Metal Nanoparticles (Ag, Au, Pd) on the Photocatalytic Activity of ZnO NPs Embedded in Renewable Castor Oil Polymer Matrices

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3468
Author(s):  
Andreea L. Chibac-Scutaru ◽  
Viorica Podasca ◽  
Daniel Timpu ◽  
Violeta Melinte
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Metal Nanoparticles ◽  
Noble Metal ◽  
Castor Oil ◽  
Nanocomposite Films ◽  
Noble Metal Nanoparticles ◽  
Zno Nps ◽  
Urethane Dimethacrylate

Hybrid polymeric materials, due to the unique combination of properties that can be obtained by the convenient variation of organic and inorganic components, represent an attractive alternative for many applications, especially photocatalysis. Herein, we report the preparation of nanocomposite films containing functionalized ZnO nanoparticles, as well as in situ photogenerated noble metal nanoparticles (Ag, Au, Pd), for the achieving of materials with enhanced photocatalytic activity under visible light. The flexible free-standing nanocomposite films were synthesized by photopolymerization of a monomer mixture (silane castor oil urethane dimethacrylate and polypropylene oxide urethane dimethacrylate) in the presence of a Irgacure 819 photoinitiator. The efficiency of ZnO NPs functionalization was established by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis, while the polymer composites were characterized by UV-Vis spectroscopy, X-ray diffraction, transmission electron microscopy and scanning electron microscopy to evidence the formation, size and distribution of the nanoparticles inside the photocrosslinked matrix. To establish the photocatalytic capacity of nanocomposite films, the decomposition of various pollutants (methyl orange, phenol, metronidazole) was monitored under visible light irradiation, the best results being obtained for Au/ZnO film. Also, the advantage of immobilizing the catalysts in a polymeric support and its recycling ability without a significant decrease in photocatalytic efficiency was analysed.

Synthesis of Noble Metal/Carbon Nanotube Composites in Supercritical Methanol

2006 ◽  
Vol 6 (3) ◽  
pp. 691-697 ◽  
Author(s):  
Zhenyu Sun ◽  
Lei Fu ◽  
Zhimin Liu ◽  
Buxing Han ◽  
Yunqi Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Metal Nanoparticles ◽  
Noble Metal ◽  
Photoelectron Spectroscopy ◽  
Noble Metal Nanoparticles ◽  
Narrow Particle Size Distribution ◽  
Supercritical Methanol ◽  
X Ray ◽  
Metal Precursors ◽  
Nanotube Composites

A simple and efficient route has been employed to deposit noble metal nanoparticles (Pt, Ru, Pt–Ru, Rh, Ru–Sn) onto carbon nanotubes (CNTs) in supercritical methanol solution. In this method, the inorganic metallic salts acted as metal precursors, and methanol as solvent as well as reductant for the precursors. The as-prepared nanocomposites were structurally and morphologically characterized by X-ray diffraction spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy, and X-ray photoelectron spectroscopy analyses. It was demonstrated that the CNTs were decorated by crystalline metal nanoparticles with uniform sizes and a narrow particle size distribution. The size and loading content of the nanoparticles on CNTs could be tuned by manipulating reaction parameters. Furthermore, the formation mechanism of the composites was also discussed.

Nanocomposites Consisting of Carbon Nanotubes and Nanoparticles of Noble Metals

2016 ◽  
Vol 879 ◽  
pp. 442-447
Author(s):  
A.D. Dobrzańska-Danikiewicz ◽  
D. Cichocki ◽  
D. Łukowiec
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
Transmission Electron Microscopy ◽  
Noble Metal ◽  
Noble Metals ◽  
Chemical Reduction ◽  
Chemical Vapour ◽  
Transmission Electron ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

In the framework of the made researches nanocomposite of CNT-NPs type (Carbon Nanotube-Nanoparticles) consisting of multiwalled carbon nanotubes coated by rhodium nanoparticles and/or palladium using the two-step indirect method: chemical reduction have been produced. In the researches high-quality multi-walled carbon nanotubes MWCNTs with a length of 100 to 500 nm and a diameter of 8 to 20 nm previously obtained in the catalytic-chemical vapour deposition CCVD have been used. Nanotubes produced within the framework of own researches contain minor amounts of metallic impurities and amorphous carbon deposits. In order to deposit the noble metal nanoparticles on the surface of carbon nanotubes functionalization of multi-walled carbon nanotubes in a mixture of H2SO4 and HNO3 acids have been used. The prepared material has been subjected chemical reduction using noble metal precursors (RhCI3, PdCl2). The characterization of the produced material including the examination of the structure, morphology, chemical composition and evaluation of the size and distribution of rhodium and/or palladium nanoparticles on the surface of carbon nanotubes has been performed using: scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS). The produced nanomaterials may be used as the active layer of sensors of chemical/biological agents.

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