Sunlight-Driving Formation and Characterization of Size-Controlled Gold Nanoparticles

2007 ◽  
Vol 7 (2) ◽  
pp. 708-711 ◽  
Author(s):  
Yonglan Luo
Keyword(s):  
Gold Nanoparticles ◽  
Sodium Citrate ◽  
Noble Metal Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron Microcopy ◽  
Uv Visible ◽  
Size Controlled

Exposing a sodium citrate-HAuCl4 aqueous solution to sunlight results in the formation of size-controlled, citrate-capped gold nanoparticles. The gold nanoparticles were characterized by UV-visible, transmission electron microscopy (TEM), scanning electron microcopy (SEM), and X-ray diffraction (XRD) spectroscopic methods. It provides a general methodologyfor the economic, convenient, mild preparation of citrate-capped noble metal nanoparticles.

Size-controlled Synthesis of Gold Nanoparticles by Thermolysis of a Gold(I)-Sulfide Complex in the Presence of Alkylamines

2009 ◽  
Vol 64 (11-12) ◽  
pp. 1305-1311 ◽  
Author(s):  
Mari Yamamoto ◽  
Yukiyasu Kashiwagi ◽  
Masami Nakamoto
Keyword(s):  
Gold Nanoparticles ◽  
Photoelectron Spectroscopy ◽  
Thermal Analyses ◽  
Controlled Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Alkyl Chains ◽  
Transmission Electron ◽  
Gas Chromatography Mass Spectroscopy ◽  
Size Controlled

A size-controlled synthesis of gold nanoparticles has been developed by the thermolysis of AuCl(SMe2) in the presence of alkylamines at 120 °C. In the procedure, the key intermediate was [Au(NH2R)2]Cl, detected by electrospray ionization (ESI) mass spectrometry. This thermally unstable intermediate was reduced by alkylamines under mild conditions to produce alkylamine-capped gold nanoparticles. The average diameters of the gold nanoparticles could be regulated in a range from 4.3 to 6.1 nm by applying primary alkylamines with alkyl chains of different lengths. Larger gold nanoparticles with diameters from 10 to 22 nm were prepared by a combination of alkylamines and alkylcarboxylic acids with various lengths of the alkyl chains. The gold nanoparticles were characterized by transmission electron microscopy (TEM), UV/Vis absorption spectroscopy, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), gas chromatography/mass spectroscopy (GC/MS), and thermogravimetric and differencial thermal analyses (TG/DTA)

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.

Ultrasonic-hydrothermal Synthesis and Characterization of Mesoporous Anatase TiO2 Microspheres

2011 ◽  
Vol 239-242 ◽  
pp. 2323-2326 ◽  
Author(s):  
Hai Bin Li ◽  
Shu Guang Chen ◽  
Wei Ming Lu ◽  
Qi Cheng Liu
Keyword(s):  
Diffuse Reflectance Spectroscopy ◽  
Tetrabutyl Titanate ◽  
X Ray Diffraction ◽  
Structure Directing Agent ◽  
X Ray ◽  
Transmission Electron ◽  
Uv Visible ◽  
Average Size ◽  
Adsorption Desorption

Mesoporous TiO2 microspheres with a combination of large surface and high crystallinity were fabricated by an ultrasonic-hydrothermal method with Octadecylamine as a structure-directing agent and tetrabutyl titanate as a precursor. The mesoporous materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption–desorption measurements, and UV–visible diffuse reflectance spectroscopy (UV-vis). Low-angle XRD and TEM images indicated that the disordered wormhole-like mesoporous architecture of TiO2 microspheres with diameters of about 200-400 nm were actually formed by agglomerization of nanoparticles with an average size of about 10nm. The analysis from N2 adsorption–desorption isotherms showed that the surface area of mesoporous sample was 204.7 m2g-1, with a pore size of 4.3 nm and pore volume of 0.263 cm3g-1 after calcined at 673 K.

Eco-Friendly Synthesis of Gold Nanoparticles by Bacillus subtilis and Their Environmental Applications

2018 ◽  
Vol 24 (8) ◽  
pp. 5942-5946 ◽  
Author(s):  
B. S Srinath ◽  
K Namratha ◽  
K Byrappa
Keyword(s):  
Gold Nanoparticles ◽  
Bacillus Subtilis ◽  
Color Change ◽  
Cost Effective ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gold Mines ◽  
The Earth ◽  
Transmission Electron ◽  
Uv Visible

Biosynthesis of gold nanoparticles (GNPs) is an eco-friendly, cost effective and nontoxic alternative to chemical and physical methods. The microbe which inhabits nearly all surfaces on the earth, an attainment typically attributed to their metabolic adaptability. The organism which resides in gold mines would be having more capability to resist against soluble gold toxicity and produce gold nanoparticles efficiently. In the present study, we report for the synthesis of GNPs by a member of Bacillus subtilis isolated from Hutti gold mine, India. The synthesis of GNPs was observed by a color change from yellow to pink and confirmed by a peak around 545 nm using a UV–visible spectroscopy. The synthesized GNPs were further characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and Transmission electron microscopy (TEM). The results show that synthesized GNPs are well dispersed and their size ranges 20–25 nm. The present work is aimed to use green synthesized GNPs as catalyst to degrade Methylene blue (MB) and these GNPs could be used to degrade toxic dyes in the environment.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Detonation Synthesis of Nano-Size Materials

1995 ◽  
Vol 418 ◽  
Author(s):  
J. Forbes ◽  
J. Davis ◽  
C. Wong
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Nucleation And Growth ◽  
Detonation Synthesis ◽  
X Ray Diffraction ◽  
Crystalline Materials ◽  
X Ray ◽  
Transmission Electron ◽  
Nano Size

AbstractThe detonation of explosives typically creates 100's of kbar pressures and 1000's K temperatures. These pressures and temperatures last for only a fraction of a microsecond as the products expand. Nucleation and growth of crystalline materials can occur under these conditions. Recovery of these materials is difficult but can occur in some circumstances. This paper describes the detonation synthesis facility, recovery of nano-size diamond, and plans to synthesize other nano-size materials by modifying the chemical composition of explosive compounds. The characterization of nano-size diamonds by transmission electron microscopy and electron diffraction, X-ray diffraction and Raman spectroscopy will also be reported.

One Step Synthesis and Characterization of Zirconia-Graphene Composites

2012 ◽  
Vol 600 ◽  
pp. 174-177 ◽  
Author(s):  
Jian Fei Xia ◽  
Zong Hua Wang ◽  
Yan Zhi Xia ◽  
Fei Fei Zhang ◽  
Fu Qiang Zhu ◽  
...  
Keyword(s):  
Synthesis And Characterization ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Graphene Composite ◽  
Transmission Electron ◽  
One Step ◽  
Ft Ir ◽  
Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.

scholarly journals Characterization of ferrite nanoparticles for preparation of biocomposites

2017 ◽  
Vol 8 ◽  
pp. 1257-1265 ◽  
Author(s):  
Urszula Klekotka ◽  
Magdalena Rogowska ◽  
Dariusz Satuła ◽  
Beata Kalska-Szostko
Keyword(s):  
Chemical Method ◽  
Ferrite Nanoparticles ◽  
Chemical Activity ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
Wet Chemical Method ◽  
X Ray ◽  
Transmission Electron ◽  
Wet Chemical

Ferrite nanoparticles with nominal composition Me0.5Fe2.5O4 (Me = Co, Fe, Ni or Mn) have been successfully prepared by the wet chemical method. The obtained particles have a mean diameter of 11–16 ± 2 nm and were modified to improve their magnetic properties and chemical activity. The surface of the pristine nanoparticles was functionalized afterwards with –COOH and –NH2 groups to obtain a bioactive layer. To achieve our goal, two different modification approaches were realized. In the first one, glutaraldehyde was attached to the nanoparticles as a linker. In the second one, direct bonding of such nanoparticles with a bioparticle was studied. In subsequent steps, the nanoparticles were immobilized with enzymes such as albumin, glucose oxidase, lipase and trypsin as a test bioparticles. The characterization of the nanoparticles was acheived by transmission electron microscopy, X-ray diffraction, energy dispersive X-ray and Mössbauer spectroscopy. The effect of the obtained biocomposites was monitored by Fourier transform infrared spectroscopy. The obtained results show that in some cases the use of glutaraldehyde was crucial (albumin).

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