Study on Dispersion and Characterization of Functionalized MWCNTs Prepared by Wet Oxidation

2014 ◽  
Vol 661 ◽  
pp. 8-13 ◽  
Author(s):  
Intan Syaffinazzilla Zaine ◽  
N.A.M. Napiah ◽  
Azmi Mohamad Yusof ◽  
A.N. Alias ◽  
A.M.M. Ali ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Relative Intensity ◽  
Colloidal Stability ◽  
Structural Defects ◽  
Wet Oxidation ◽  
Defect Level ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Functionalized Mwcnts

The MWCNTs was functionalized by refluxing commercial MWCNTs (a-MWCNTs) in concentrated HNO3/H2SO4 (3:1 v/v) at 100°C for 6 hours. The dispersion of a-MWCNTs and functionalized MWCNTs (f-MWCNTs) were observed after 1 hour sonication in ethanol. Both samples were characterized by UV-vis spectroscopy for dispersion behavior. The dried f-MWCNTs and a-MWCNTs were characterized by Raman spectroscopy to estimate the defect level. The morphology of the samples were analyzed by Transmission Electron Microscopy (TEM). The f-MWCNTs was well dispersed in ethanol within 2 weeks of observations period. The colloidal stability of a-MWCNTs was low as it was easily sediment after 24 hours. The UV-vis spectra of f-MWCNTs show maximum absorbance at 250 nm meanwhile no absorbance was observed for a-MWCNTs. Analysis from Raman spectrum shows that the f-MWCNTs have relative intensity of 1.101 which is higher than a-MWCNTs that have relative intensity of 0.935. The image from TEM revealed that the f-MWCNTs have structural defects and the absence of amorphous carbon on sidewall meanwhile the a-MWCNTs indicate otherwise.

scholarly journals Synthesis and characterization of Fe, Co, and Ni colloids in 2-mercaptoethanol

2020 ◽  
Vol 10 ◽  
pp. 184798042096688
Author(s):  
Galo Cárdenas-Triviño ◽  
Sergio Triviño-Matus
Keyword(s):  
Electron Microscopy ◽  
Electron Diffraction ◽  
Colloidal Dispersions ◽  
Synthesis And Characterization ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Chemical Liquid Deposition ◽  
Liquid Deposition

Metal colloids in 2-mercaptoethanol using nanoparticles (NPs) of iron (Fe), cobalt (Co), and nickel (Ni) were prepared by chemical liquid deposition method. Transmission electron microscopy, electron diffraction, UV-VIS spectroscopy, and scanning electron microscopy with electron dispersive X-ray spectroscopy characterized the resulting colloidal dispersions. The NPs exhibited sizes with ranges from 9.8 nm for Fe, 3.7 nm for Co, and 7.2 nm for Ni. The electron diffraction shows the presence of the metals in its elemental state Fe (0), Co (0), and Ni (0) and also some compounds FeO (OH), CoCo2S4, and NiNi2S4.

The Aggregation Study and Characterization of Silver Nanoparticles

2017 ◽  
Vol 263 ◽  
pp. 165-169
Author(s):  
Silvia Chowdhury ◽  
Faridah Yusof ◽  
Nadzril Sulaiman ◽  
Mohammad Omer Faruck
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Particle Size ◽  
Silver Nanoparticles ◽  
Absorption Spectrum ◽  
Average Particle Size ◽  
Average Particle ◽  
Transmission Electron ◽  
Vis Spectroscopy

In this article, we have studied the process of silver nanoparticles (AgNPs) aggregation and to stop aggregation 0.3% Polyvinylpyrrolidone (PVP) was used. Aggregation study carried out via UV-vis spectroscopy and it is reported that the absorption spectrum of spherical silver nanoparticles were found a maximum peak at 420 nm wavelength. Furthermore, Transmission Electron Microscopy (TEM) were used to characterized the size and shape of AgNPs, where the average particle size is around 10 to 25 nm in diameter and the AgNPs shape is spherical. Next, Dynamic Light Scattering (DLS) were used, owing to observed size distribution and self-correlation of AgNPs.

scholarly journals Preparation and characterization of highly blue emitting fluorescent carbon nano-dots using Pongammia pinnata fresh leaves

2021 ◽  
Author(s):  
Govindaraju K ◽  
K. Vijai Anand ◽  
S. Muthamilselvan ◽  
M. Kannan ◽  
M. Elanchezhiyan
Keyword(s):  
Electron Microscopy ◽  
Water Soluble ◽  
Hydrothermal Technique ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Ft Ir ◽  
Average Size ◽  
Soluble Carbon ◽  
Ft Ir Spectroscopy

Abstract In this study, a simple environmental benign approach have been adopted for the preparation of highly luminescent (blue emitting) water soluble carbon nano-dots using Pongammia pinnata (Pp) leaves via hydrothermal technique. The prepared Pp-carbon nano- dots were characterized using UV-vis spectroscopy, fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM) and dynamic light scattering (DLS) measurements. The Pp-carbon nano-dots are spherical in shape with an average size of 32 nm.

Preparation and characterization of novel magnetic nanocomposite-bonded metalloporphyrins as biomimetic nanocatalysts

2010 ◽  
Vol 14 (09) ◽  
pp. 825-831 ◽  
Author(s):  
Chang-Xiang Liu ◽  
Qiang Liu ◽  
Can-Cheng Guo ◽  
Ze Tan
Keyword(s):  
Electron Microscopy ◽  
Magnetic Nanocomposite ◽  
Magnetic Nanocomposites ◽  
Solid Mixture ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Amidation Reaction ◽  
Bet Method ◽  
Input Ratio

In this work, novel magnetic nanocomposite-bonded metalloporphyrins were synthesized by an effective silanation approach between 3-aminopropyltriethoxysilane derivatized metalloporphyrins and silica-coated magnetic Fe3O4 nanoparticles. The initial metalloporphyrin derivatives were synthesized by the amidation reaction of metalloporphyrin acyl chloride with 3-aminopropyltriethoxysilane. After the metalloporphyrin derivatives were adsorbed on the surface of silica-coated magnetic Fe3O4 nanoparticles, the solid mixture was heated under vacuum at 110 °C for 3 h and then thoroughly washed with chloroform. The obtained magnetic nanocomposite-bonded metalloporphyrins were characterized by elemental analyzer, low-temperature N2 adsorption (BET method), transmission electron microscopy, UV-vis spectroscopy, and infrared spectroscopy. Interestingly, using this particular silanation method, metalloporphyrins could be quantitative-immobilized in magnetic nanocomposites by controlling the input ratio of metalloporphyrins and silica-coated magnetic Fe3O4 nanoparticles. The excellent catalytic activity and recyclability of the magnetic nanocomposite-bonded metalloporphyrins were demonstrated in the cyclohexane oxidation with iodosylbenzene.

scholarly journals Phytochemical Synthesis and Preliminary Characterization of Silver Nanoparticles Using Hesperidin

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Anish Stephen ◽  
Sankar Seethalakshmi
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
Reaction Time ◽  
Silver Nanoparticle ◽  
Size Range ◽  
Transmission Electron ◽  
Vis Spectroscopy

This paper is the first of its kind for development of rapid and ecofriendly method for synthesis of silver nanoparticles from aqueous solution of silver nitrate using the flavonoid “hesperidin” and optimization of the methodology. There is formation of stable spherical silver nanoparticles in the size range of 20–40 nm. Optimization of methodology in terms of concentration of reactants and pH of the reaction mixture reduced the reaction time for silver nanoparticle formation to 2 mins. Silver nanoparticles (AgNPs) were characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). UV-vis spectroscopy derived spectrum demonstrated a peak of 430 nm which corresponds to the plasmon absorbance of silver nanoparticles. Transmission electron microscopy revealed spherical shaped silver nanoparticles in the size range of 20–40 nm.

Quantitative Characterization of Internal Boundaries — What Can Be Achieved with Electron Microscopy?

2001 ◽  
Vol 7 (S2) ◽  
pp. 236-237
Author(s):  
Christian Elsasser ◽  
Manfred Rühle
Keyword(s):  
Electron Microscopy ◽  
Functional Materials ◽  
Transport Processes ◽  
Structural Defects ◽  
Quantitative Characterization ◽  
Transmission Electron ◽  
Deformation And Fracture ◽  
Experimental Approaches ◽  
Physical Phenomena

Internal boundaries in crystalline microstructures, like polycrystals, thin-film or multi-layer composites, essentially control many important material properties and physical phenomena, such as mechanical deformation and fracture, transport processes or phase transformations. This influence is originating from the local atomistic and electronic structures at the boundaries. Hence, for a. science-based technological design and optimisation of structural and functional materials it is of paramount importance to characterize and understand the structure, chemistry and bonding at interfaces.Transmission electron microscopy (TEM) has matured to one of the most successful experimental approaches for the analysis of extended structural defects like dislocations and interfaces. This presentation discusses scientific and technological ingredients of TEM for quantitative characterisations on the microscopic level. For selected model cases of internal interfaces it illustrates recent achievements of both experiment and theory. A variety of interface properties and corresponding TEM techniques for their characterisation are summarized in TABLE 1.

scholarly journals Size and shape controlled synthesis of CdS and ZnS nanoparticles and their applications in photodegradation of organic dyes

2021 ◽  
Author(s):  
Babak Kaboudin ◽  
Meysam Kyomarzi ◽  
Foad Kazemi
Keyword(s):  
Electron Microscopy ◽  
Alkyl Chain ◽  
Organic Dyes ◽  
Cds Nanoparticles ◽  
Zns Nanoparticles ◽  
Sem Images ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Means Of Transmission

Abstract Different size and shapes of CdS and ZnS nanoparticles have been synthesized, characterized and studied for photodegradation of organic dyes. In this study, effect of alkyl chain of dithiocarbamates was investigated for the size and shaped controlled CdS and ZnS nanoparticles. A thorough structural characterization of nanoparticles has been carried out by means of transmission electron microscopy (TEM), scanning electron microscopy (SEM) images, EDS, XRD, and UV/vis spectroscopy. Results showed that the alkyl chain in dithiocarbamate complexes of zinc and cadmium systems plays a significant role in the final morphology of the CdS and ZnS nanoparticles. A photocatalytic degradation of UV-irradiated Methylene Blue solutions in the presence of ZnS and CdS nanoparticles was studied in order to examine the nanoparticles influence on photodegradation rates.

Cryomicroscopy of multiphase latices

1991 ◽  
Vol 49 ◽  
pp. 1060-1061
Author(s):  
O. L. Shaffer ◽  
M.S. El-Aasser ◽  
C. L. Zhao ◽  
M. A. Winnik ◽  
R. R. Shivers
Keyword(s):  
Electron Microscopy ◽  
Radiation Damage ◽  
Freeze Fracture ◽  
Particle Morphology ◽  
Second Stage ◽  
Transmission Electron ◽  
Important Approach ◽  
Carbon Coated ◽  
Preparation Techniques

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.

Applications of Transmission Electron Microscopy in the Characterization of Metal Machinability

1968 ◽  
Vol 26 ◽  
pp. 442-443 ◽  
Author(s):  
L.E. Murr ◽  
A.B. Draper
Keyword(s):  
Electron Microscopy ◽  
State Physics ◽  
Test Material ◽  
Milling Machine ◽  
Rotary Table ◽  
Solid State Physics ◽  
Materials Properties ◽  
Transmission Electron ◽  
Selection Of

The industrial characterization of the machinability of metals and alloys has always been a very arbitrarily defined property, subject to the selection of various reference or test materials; and the adoption of rather naive and misleading interpretations and standards. However, it seems reasonable to assume that with the present state of knowledge of materials properties, and the current theories of solid state physics, more basic guidelines for machinability characterization might be established on the basis of the residual machined microstructures. This approach was originally pursued by Draper; and our presentation here will simply reflect an exposition and extension of this research.The technique consists initially in the production of machined chips of a desired test material on a horizontal milling machine with the workpiece (specimen) mounted on a rotary table vice. A single cut of a specified depth is taken from the workpiece (0.25 in. wide) each at a new tool location.

Interface structures in polycrystalline ceramic materials

1986 ◽  
Vol 44 ◽  
pp. 468-471
Author(s):  
K. J. Morrissey
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Physical And Mechanical Properties ◽  
High Resolution Electron Microscopy ◽  
Ceramic Materials ◽  
Polycrystalline Materials ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Interface Structures

Grain boundaries and interfaces play an important role in determining both physical and mechanical properties of polycrystalline materials. To understand how the structure of interfaces can be controlled to optimize properties, it is necessary to understand and be able to predict their crystal chemistry. Transmission electron microscopy (TEM), analytical electron microscopy (AEM,), and high resolution electron microscopy (HREM) are essential tools for the characterization of the different types of interfaces which exist in ceramic systems. The purpose of this paper is to illustrate some specific areas in which understanding interface structure is important. Interfaces in sintered bodies, materials produced through phase transformation and electronic packaging are discussed.

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