Preliminary study on the preparation of graphene from coke with a combined chemical and physical routine

2020 ◽  
Vol 117 (6) ◽  
pp. 605
Author(s):  
Minmin Sun ◽  
Jianliang Zhang ◽  
Minghao Li ◽  
Wei Xiong ◽  
Kejiang Li ◽  
...  
Keyword(s):  
Carbon Nanomaterials ◽  
Materials Science ◽  
Low Cost ◽  
Production Costs ◽  
Metallurgical Coke ◽  
Carbon Powder ◽  
X Ray ◽  
Transmission Electron ◽  
Facile Fabrication ◽  
Microscopic Morphology

As a revolutionary material with optical, electrical and mechanical properties, graphene has high production costs in terms of materials science, micro-nano processing, energy, biomedicine and drug delivery. To explore the low-cost materials for the synthesis of carbon nanomaterials, a method for the affordable and facile fabrication by metallurgical coke fine was demonstrated. The demineralized coke ultrafine powder (< 10 µm) was oxidized, and then treated with a combination of thermal exfoliation and solvent exfoliation. The resulting carbon powder were characterized with microscopic morphology, the defects and type of carbon and the carbon structural order by Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Photoemission Spectroscopy (XPS), Raman Spectroscopy and X-ray Diffraction (XRD). The graphene prepared by chemical-physical routine with demineralized metallurgical coke superfine powder exhibits similar characteristics to those prepared by graphite traditionally, which provides an economical and environmentally friendly method for the preparation of graphene materials.

X-ray mapping without STEM

1994 ◽  
Vol 52 ◽  
pp. 508-509
Author(s):  
Judith M. Brock ◽  
Max T. Otten
Keyword(s):  
Life Science ◽  
Materials Science ◽  
Chemical Elements ◽  
Full Description ◽  
Scanning System ◽  
Elemental Distribution ◽  
X Ray ◽  
Transmission Electron ◽  
Distribution Of Elements ◽  
Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

scholarly journals Green Synthesis of Silver and Gold Nanoparticles via Sargassum serratifolium Extract for Catalytic Reduction of Organic Dyes

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 347
Author(s):  
Beomjin Kim ◽  
Woo Chang Song ◽  
Sun Young Park ◽  
Geuntae Park
Keyword(s):  
Gold Nanoparticles ◽  
Green Synthesis ◽  
Catalytic Reduction ◽  
Organic Dyes ◽  
Low Cost ◽  
Inorganic Nanoparticles ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Sargassum Serratifolium

The green synthesis of inorganic nanoparticles (NPs) using bio-materials has attained enormous attention in recent years due to its simple, eco-friendly, low-cost and non-toxic nature. In this work, silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were synthesized by the marine algae extract, Sargassum serratifolium (SS). The characteristic studies of bio-synthesized SS-AgNPs and SS-AuNPs were carried out by using ultraviolet–visible (UV–Vis) absorption spectroscopy, dynamic light scattering (DLS), high-resolution transmission electron microscope (HR-TEM), selected area electron diffraction (SAED), energy-dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Phytochemicals in the algae extract, such as meroterpenoids, acted as a capping agent for the NPs’ growth. The synthesized Ag and Au NPs were found to have important catalytic activity for the degradation of organic dyes, including methylene blue, rhodamine B and methyl orange. The reduction of dyes by SS-AgNPs and -AuNPs followed the pseudo-first order kinetics.

Low-cost thermo-chemical process of TiO2 powder purification: Study of iterative gettering effect

2021 ◽  
Author(s):  
Nesrine Jaouabi ◽  
Wala Medfai ◽  
Marouan Khalifa ◽  
Rabia Zaghouani ◽  
Hatem Ezzaouia
Keyword(s):  
Porous Layer ◽  
Sacrificial Layer ◽  
Low Cost ◽  
Nir Spectroscopy ◽  
Tio2 Powder ◽  
X Ray Diffraction ◽  
X Ray ◽  
Density Reduction ◽  
Transmission Electron ◽  
Layer Effect

The titanium dioxide (TiO2) purity is very important for the TiO2-based applications making essential the impurities density reduction. In this study, we propose an efficient purification process of TiO2 powder in order to reduce impurities. The low-cost proposed approach is based on an iterative gettering (IG) process combining three main steps: (1) a porous TiO2 sacrificial layer formation (p-TiO2), (2) a rapid thermal annealing (RTA) of p-TiO2 powder in an infrared oven at 950°C under air permitting the residual impurities diffusion to the porous layer surface and (3) etching in acid solution to remove the porous layer. Effect of the proposed gettering process on purification efficiency was evaluated by different characterization techniques such as the transmission electron microscopy (TEM), the energy dispersive x-ray spectroscopy (EDX), the UV–Visible-NIR spectroscopy, the X-ray diffraction (XRD) and atomic absorption spectroscopy (AAS). The obtained results showed the efficient removal of metal impurities, such as Cu, Al, P, and Fe confirming the efficiency of the process improving the purity from 89% to 99.96%.

Solution-Based Synthesis of Magnesium Oxide Nanorods

1999 ◽  
Vol 581 ◽  
Author(s):  
Q. Wei ◽  
C.M. Lieber
Keyword(s):  
Electron Microscopy ◽  
Magnesium Oxide ◽  
Magnesium Chloride ◽  
Low Cost ◽  
Industrial Applications ◽  
Transformation Process ◽  
Matrix Composites ◽  
X Ray ◽  
Transmission Electron ◽  
Oxide Nanorods

ABSTRACTA solution-based synthesis route was developed to produce large quantities of MgO nanorods. Hydrated basic magnesium chloride, which has needle-like crystal structure, was used as a precursor. A subsequent two-step transformation process with magnesium hydroxide as an intermediate product was used to preserve the morphology of the precursor to yield magnesium oxide nanorods. Scanning electron microscopy, powder X-ray diffraction and energy dispersive X-ray spectroscopy show that the products are very pure (>95%) crystalline MgO nanorods with diameters from 40 nm to 200 nm and lengths 10 microns or longer. High-resolution transmission electron microscopy and electron diffraction further reveal that these MgO nanorods are single crystals and that the rod axis is along the <110> crystal direction. A model for the structural transformation from hydrated basic magnesium chloride to magnesium oxide has been developed and compared to our experimental results. This solution-based process can be easily scaled-up, and is a low-cost source of pure magnesium oxide nanorods needed in many industrial applications, for example, as reinforcing agents in matrix composites and as flux-pinning centers in high-TC superconductors.

Corrosion protection performance of titania nanoparticles filled poly(4-methyl-5-vinylthiazole) applied on mild steel in 3.5% sodium chloride solution

2020 ◽  
pp. 875608792093930 ◽  
Author(s):  
I Pugazhenthi ◽  
S Mohammed Ghouse
Keyword(s):  
Mild Steel ◽  
Electrochemical Impedance ◽  
Low Cost ◽  
Nano Particles ◽  
Titania Nanoparticles ◽  
X Ray Diffraction ◽  
Corrosive Media ◽  
X Ray ◽  
Polymer Hybrid ◽  
Transmission Electron

Mild steel materials have wide applications in marine construction, because they are low cost, available and easy to handle. However, they have to be protected from corrosive media by coating with polymer hybrid materials. This paper focuses on the anticorrosive properties of poly(4-methyl-5-vinylthiazole) PVTZ coatings on mild steel. Further the coating resistance is enhanced by incorporating Titania Nano particles (TiO2NPs). The nanoparticles were evaluated using X-ray diffraction studies (XRD) and transmission electron microscopy (TEM). PVTZ and its TiO2 nanocomposite were coated on mild steel. Their anticorrosive behavior was analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5% (w/v) NaCl.

Low-Cost Synthesis and Morphology Control of Magnesium Oxysulfate Hydrate Whiskers

2014 ◽  
Vol 936 ◽  
pp. 986-991
Author(s):  
Chuan Hui Gao ◽  
Li Ding ◽  
Yu Min Wu ◽  
Chuan Xing Wang ◽  
Jun Xu
Keyword(s):  
Electron Microscope ◽  
Raw Materials ◽  
Low Cost ◽  
Hydrothermal Process ◽  
Control Agent ◽  
Raw Material ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Magnesium Oxysulfate

A low-cost raw material, bittern obtained from the production process of sea salt, was used to prepare magnesium oxysulfate hydrate (MgSO4·5Mg (OH)2·2H2O, abbreviated as 152MOS) whiskers via hydrothermal synthesis with ammonia and magnesium sulfate as the other starting raw materials. The bittern was firstly filtered and then used directly without de-coloring. X-ray powder diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) were employed to investigate the composition and morphology of the products. It was found that the 152MOS whiskers synthesized from bittern at 190°C for 3 hours exhibited fanlike morphology. The formation of the fanlike whiskers was inhibited and most of the whiskers presented as single fibers when ethanol was used as crystal control agent in the hydrothermal process. From the two-dimensional steps observed at tips of the whiskers, a possible growth mechanism was speculated that it was the extension of dislocations that made the growth of the whiskers.

The Effect of Focused Ion Beam (Fib) Specimen Geometry on X-Ray Fluorescence During Energy Dispersive X-Ray Spectroscopy (EDS) Analysis in the Transmission Electron Microscope (TEM)

1998 ◽  
Vol 4 (S2) ◽  
pp. 856-857
Author(s):  
David M. Longo ◽  
James M. Howe ◽  
William C. Johnson
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Focused Ion Beam ◽  
Materials Science ◽  
Bulk Material ◽  
Ion Beam ◽  
Energy Dispersive ◽  
Specimen Preparation ◽  
X Ray ◽  
Transmission Electron

The focused ion beam (FIB) has become an indispensable tool for a variety of applications in materials science, including that of specimen preparation for the transmission electron microscope (TEM). Several FIB specimen preparation techniques have been developed, but some problems result when FIB specimens are analyzed in the TEM. One of these is X-ray fluorescence from bulk material surrounding the thin membrane in FIB-prepared samples. This paper reports on a new FIB specimen preparation method which was devised for the reduction of X-ray fluorescence during energy dispersive X-ray spectroscopy (EDS) in the TEM.Figure 1 shows three membrane geometries that were investigated in this study on a single-crystal Si substrate with a RF sputter-deposited 50 nm Ni film. Membrane 1 is the most commonly reported geometry in the literature, with an approximately 20 urn wide trench and a membrane having a single wedge with a 1.5° incline.

scholarly journals Facile Fabrication of CeO2/Electrochemically Reduced Graphene Oxide Nanocomposites for Vanillin Detection in Commercial Food Products

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1356 ◽  
Author(s):  
Xue Nie ◽  
Rui Zhang ◽  
Zheng Tang ◽  
Haiyan Wang ◽  
Peihong Deng ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Linear Sweep Voltammetry ◽  
X Ray ◽  
Transmission Electron ◽  
Reduced Graphene ◽  
Electrochemically Reduced Graphene Oxide ◽  
Wide Range ◽  
Facile Fabrication

In this paper, CeO2 nanoparticles were synthesized by the solvothermal method and dispersed uniformly in graphene oxide (GO) aqueous solution by ultrasonication. The homogeneous CeO2-GO dispersion was coated on the surface of a glassy carbon electrode (GCE), and the CeO2/electrochemically reduced graphene oxide modified electrode (CeO2/ERGO/GCE) was obtained by potentiostatic reduction. The results of X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) showed that CeO2 nanocrystals were uniformly coated by gossamer like ERGO nanosheets. The electrochemical behavior of vanillin on the CeO2/ERGO/GCE was studied by cyclic voltammetry (CV). It was found that the CeO2/ERGO/GCE has high electrocatalytic activity and good electrochemical performance for vanillin oxidation. Using the second derivative linear sweep voltammetry (SDLSV), the CeO2/ERGO/GCE provides a wide range of 0.04–20 µM and 20 µM–100 µM for vanillin detection, and the detection limit is estimated to be 0.01 µM after 120 s accumulation. This method has been successfully applied to the vanillin detection in some commercial foods.

scholarly journals A Novel X-Ray Radiation Sensor Based on Networked SnO2 Nanowires

2019 ◽  
Vol 9 (22) ◽  
pp. 4878 ◽  
Author(s):  
Jae-Hun Kim ◽  
Ali Mirzaei ◽  
Hyoun Woo Kim ◽  
Hong Joo Kim ◽  
Phan Quoc Vuong ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Low Cost ◽  
X Rays ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Radiation Sensor ◽  
Sno2 Nanowires ◽  
Radiation Sensors

X-Ray radiation sensors that work at room temperature are in demand. In this study, a novel, low-cost real-time X-ray radiation sensor based on SnO2 nanowires (NWs) was designed and tested. Networked SnO2 NWs were produced via the vapor–liquid–solid technique. X-ray diffraction (XRD), transmission electron microscopy (TEM) and field emission scanning electron microscopy (SEM) analyses were used to explore the crystallinity and morphology of synthesized SnO2 NWs. The fabricated sensor was exposed to X-rays (80 kV, 0.0–2.00 mA) and the leakage current variations were recorded at room temperature. The SnO2 NWs sensor showed a high and relatively linear response with respect to the X-ray intensity. The X-ray sensing results show the potential of networked SnO2 NWs as novel X-ray sensors.

Novel synthesis of AlN nanowires with controlled diameters

2001 ◽  
Vol 16 (11) ◽  
pp. 3133-3138 ◽  
Author(s):  
Jun Liu ◽  
X. Zhang ◽  
Yingjiu Zhang ◽  
Rongrui He ◽  
Jing Zhu
Keyword(s):  
Electron Microscopy ◽  
Carbon Nanotubes ◽  
High Efficiency ◽  
Low Cost ◽  
X Ray Diffraction ◽  
Synthesis Mechanism ◽  
X Ray ◽  
Novel Synthesis ◽  
Transmission Electron ◽  
New Synthesis

A relatively low-cost, high-efficiency method is reported to synthesize AlN nanowires, using carbon nanotubes as templates. The AlN nanowires were fabricated at 1100 °C, for 60 min. The diameters of the product could be roughly controlled by the sizes of carbon nanotubes selected as starting materials. The AlN nanowires obtained were among the thinnest ever known. X-ray diffraction, selected-area diffraction, energy dispersive spectroscopy, and high-resolution transmission electron microscopy, etc. were employed to characterize the products, which were found to be single crystals with some defects. The axes of the nanowires are normal to {1010} crystal planes. A new synthesis mechanism is proposed.

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