scholarly journals Sensitivity of Mesoporous CoSb2O6Nanoparticles to Gaseous CO and C3H8at Low Temperatures

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Héctor Guillén-Bonilla ◽  
Lorenzo Gildo-Ortiz ◽  
M. de la L. Olvera-Amador ◽  
Jaime Santoyo-Salazar ◽  
Verónica M. Rodríguez-Betancourtt ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Gas Sensors ◽  
Low Temperatures ◽  
Cobalt Nitrate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Precursor Material ◽  
Means Of Transmission ◽  
Average Size

Mesoporous CoSb2O6nanoparticles, synthesized through a nonaqueous method (using cobalt nitrate, antimony trichloride, ethylenediamine, and ethanol as a solvent), were tested to establish their sensitivity to CO and C3H8atmospheres at relatively low temperatures. The precursor material was dried at 200°C and calcined at 600°C. X-ray diffraction and scanning electron microscopy were employed to verify the existence of crystal phases (P42/mnm) and the morphology of this trirutile-type CoSb2O6oxide. Pyramidal and cubic shaped crystals (average size: 41.1 nm), embedded in the material’s surface, were identified. Mesopores (average size: 6.5 nm) on the nanoparticles’ surface were observed by means of transmission electron microscopy. The best sensitivity of the CoSb2O6in a CO atmosphere was at the relatively low temperatures of 250 and 350°C, whereas, in a C3H8atmosphere, the sensitivity increased uniformly with temperature. These results encourage using the CoSb2O6nanoparticles as gas sensors.

scholarly journals Formation of ZnO/Zn0.5Cd0.5Se Alloy Quantum Dots in the Presence of High Oleylamine Contents

Nanomaterials ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 999
Author(s):  
Yi-An Chen ◽  
Kuo-Hsien Chou ◽  
Yi-Yang Kuo ◽  
Cheng-Ye Wu ◽  
Po-Wen Hsiao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Quantum Dots ◽  
Particle Size ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Alloy Quantum Dots ◽  
First Time

To the best of our knowledge, this report presents, for the first time, the schematic of the possible chemical reaction for a one-pot synthesis of Zn0.5Cd0.5Se alloy quantum dots (QDs) in the presence of low/high oleylamine (OLA) contents. For high OLA contents, high-resolution transmission electron microscopy (HRTEM) results showed that the average size of Zn0.5Cd0.5Se increases significantly from 4 to 9 nm with an increasing OLA content from 4 to 10 mL. First, [Zn(OAc)2]–OLA complex can be formed by a reaction between Zn(OAc)2 and OLA. Then, Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) data confirmed that ZnO is formed by thermal decomposition of the [Zn(OAc)2]–OLA complex. The results indicated that ZnO grew on the Zn0.5Cd0.5Se surface, thus increasing the particle size. For low OLA contents, HRTEM images were used to estimate the average sizes of the Zn0.5Cd0.5Se alloy QDs, which were approximately 8, 6, and 4 nm with OLA loadings of 0, 2, and 4 mL, respectively. We found that Zn(OAc)2 and OLA could form a [Zn(OAc)2]–OLA complex, which inhibited the growth of the Zn0.5Cd0.5Se alloy QDs, due to the decreasing reaction between Zn(oleic acid)2 and Se2−, which led to a decrease in particle size.

Synthesis of Carbon Nanosphere at Low Temperatures Based on Bamboo Fiber

2019 ◽  
Vol 966 ◽  
pp. 163-168 ◽  
Author(s):  
Yulia Kirana Lahsmin ◽  
Dahlang Tahir ◽  
Bualkar Abdullah ◽  
Sultan Ilyas ◽  
Inayatul Mutmainna
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Low Temperatures ◽  
Potassium Hydroxide ◽  
Bamboo Fiber ◽  
X Ray Diffraction ◽  
Activation Temperature ◽  
X Ray ◽  
Transmission Electron ◽  
Bamboo Fibers

Carbon Nanosphere (CNs) has been successfully synthesized from bamboo fibers at low temperatures by carbonization and activation. For activation used Potassium Hydroxide (KOH) at temperature 105°C, 155°C, 205°C, 255°C and 305°C. X-Ray Diffraction (XRD) spectra shows hexagonal and amorphous phase and Fourier Transform Infrared (FTIR) spectra shows decrease C-O bond with increasing activation temperature. Transmission Electron Microscopy (TEM) image for activation temperature of 105°C confirmed that sources the formation of Carbon Nanosphere. In this study shows bamboo fiber has a high potential as a carbon nanosphere material.

scholarly journals Synthesis of Flower-Like Cu2ZnSnS4Nanoflakes via a Microwave-Assisted Solvothermal Route

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Fei Long ◽  
Shuyi Mo ◽  
Yan Zeng ◽  
Shangsen Chi ◽  
Zhengguang Zou
Keyword(s):  
Electron Microscopy ◽  
Raman Scattering ◽  
Zinc Acetate Dihydrate ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Direct Band ◽  
Xrd Patterns ◽  
Average Size

Flower-like Cu2ZnSnS4(CZTS) nanoflakes were synthesized by a facile and fast one-pot solution reaction using copper(II) acetate monohydrate, zinc acetate dihydrate, tin(IV) chloride pentahydrate, and thiourea as starting materials. The as-synthesized samples were characterized by X-ray diffraction (XRD), Raman scattering analysis, field emission scanning electron microscopy (FESEM) equipped with an energy dispersion X-ray spectrometer (EDS), transmission electron microscopy (TEM), and UV-Vis absorption spectra. The XRD patterns shown that the as-synthesized particles were kesterite CZTS and Raman scattering analysis and EDS confirmed that kesterite CZTS was the only phase of product. The results of FESEM and TEM show that the as-synthesized particles were flower-like morphology with the average size of 1~2 μm which are composed of 50 nm thick nanoflakes. UV-Vis absorption spectrum revealed CZTS nanoflakes with a direct band gap of 1.52 eV.

Receiving Copper Nanoparticles: Experiment and Modelling

2019 ◽  
Vol 288 ◽  
pp. 140-147 ◽  
Author(s):  
Andrey V. Nomoev ◽  
Erzhena C. Khartaeva ◽  
Natalia V. Yumozhapova ◽  
Tumen G. Darmaev ◽  
S.P. Bardakhanov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Copper Nanoparticles ◽  
Pure Copper ◽  
Current Strength ◽  
X Ray Diffraction ◽  
X Ray ◽  
Embedded Atom ◽  
Transmission Electron ◽  
Average Size

The copper nanoparticles were obtained by evaporating the metal by the relativistic electron beam. The average size of synthesized particles was about 120 nm. They were characterized by X-ray diffraction, transmission electron microscopy. The results of the X-ray diffraction showed high content of the pure copper for closed setup with an inert gas. Transmission electron microscopy cleared some particles to have an icosahedral structure. These nanoparticles were obtained when the target was exposed by the beam with the highest current strength used in the experiment and the highest cooling of the copper vapor. The process of copper nanoparticle formation by the molecular dynamic method using EAM – potentials (potentials in the Embedded Atom Method form) was studied.

scholarly journals Состав, электронное и атомное строение наночастиц палладия при различных концентрациях металла в матрице полиэтилена

2020 ◽  
Vol 46 (7) ◽  
pp. 20
Author(s):  
С.С. Подсухина ◽  
А.В. Козинкин ◽  
В.Г. Власенко ◽  
Г.Ю. Юрков ◽  
О.В. Попков
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Palladium Nanoparticles ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coordination Numbers ◽  
Transmission Electron ◽  
High Pressure Polyethylene ◽  
Average Size ◽  
X Ray Absorption

The composition, electronic and atomic structure of palladium nanoparticles stabilized in high pressure polyethylene (with palladium concentrations of 10 and 20 mass%) were studied by transmission electron microscopy, X-ray diffraction, and X-ray absorption spectroscopy. It was found that nanoparticles consist of metal (Pd) and oxide (Pd2O3) components, and their average size and coordination numbers for first Pd coordination sphere decrease(from 7 to 6 nm and from 7 to 5.7, respectively) with a decrease in metal concentration.

scholarly journals Effect of Growth Temperature and Time on Morphology and Gas Sensitivity of Cu2O/Cu Microstructures

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Ling Wu ◽  
Lun Zhang ◽  
Zhipeng Xun ◽  
Guili Yu ◽  
Liwei Shi
Keyword(s):  
Electron Microscopy ◽  
Gas Sensors ◽  
Gas Sensing ◽  
Spherical Particles ◽  
X Ray Diffraction ◽  
Gas Sensitivity ◽  
X Ray ◽  
Transmission Electron ◽  
Wide Range ◽  
Gas Response

A facile hydrothermal synthesis with CuSO4as the copper source was used to prepare micro/nano-Cu2O. The obtained samples have been characterized by X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). With increasing the reaction temperature and time, the final products were successively Cu2O octahedron microcrystals, Cu2O/Cu composite particles, and a wide range of Cu spherical particles. The gas sensitivity of products towards ethanol and acetone gases was studied. The results showed that sensors prepared with Cu2O/Cu composites synthesized at 65°C for 15 min exhibited optimal gas sensitivity. The gas sensing mechanism and the effect of Cu in the enhanced gas response were also elaborated. The excellent gas sensitivity indicates that Cu2O/Cu composites have potential application as gas sensors.

scholarly journals Preparation of hcp and fcc Ni and Ni/NiO Nanoparticles Using a Citric Acid Assisted Pechini-Type Method

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
L. A. García-Cerda ◽  
K. M. Bernal-Ramos ◽  
Sagrario M. Montemayor ◽  
M. A. Quevedo-López ◽  
R. Betancourt-Galindo ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Nio Nanoparticles ◽  
X Ray Diffraction ◽  
Calcination Time ◽  
Thermal Methods ◽  
Type Method ◽  
X Ray ◽  
Transmission Electron ◽  
Precursor Material

The preparation and characterization of hcp and fcc Ni and Ni/NiO nanoparticles is reported. Ni and Ni/NiO nanoparticles were obtained starting from a precursor material prepared using a citric assisted Pechini-type method and, then, followed by a calcination of the precursor in air at either 400 or 600°C for different times. The precursor was analyzed using thermogravimetric and differential thermal methods (TGA-DTA), and the resulting nanoparticles were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and vibrational sample magnetometry. Nanoparticles showed a phase transformation for Ni from hcp to fcc and/or to fcc NiO structure as the calcination time increased. The influence of the phase transition and the formation of NiO on the magnetic properties of the samples are discussed.

scholarly journals Electrospinning Synthesis of Fe3O4/Eu(DBM)3phen/PVP Multifunctional Microfibers and Their Structure, Luminescent and Magnetic properties

2021 ◽  
Author(s):  
Ruifei Qin ◽  
lina liu
Keyword(s):  
Electron Microscopy ◽  
Magnetic Properties ◽  
Electrospinning Process ◽  
Europium Complex ◽  
X Ray Diffraction ◽  
Excitation Spectra ◽  
X Ray ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
Average Size

Abstract Multifunctional Fe3O4/Eu(DBM)3phen/PVP ((DBM: dibenzoylmethane, phen: 1,10-phenanthroline, PVP: polyvinyl pyrrolidone) microfibers were constructed by simple electrospinning process. The structure and morphology of the microfibers were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images. The diameters of pure PVP microfibers and the microfibers doped only with Fe3O4 nanoparticles (NPs) were uniformly distributed, with an average size of about 360 nm. When 3% Eu(DBM)3phen complex and Fe3O4 NPs were both added to the precursor for electrospinning, the microfibers became very inhomogeneous in diameter. The photoluminescent properties of pure Eu(DBM)3phen complex and composite microfibers were also studied. The characteristic emission peaks of Eu3+ appeared in the composite microfibers. The intensities of emission and excitation spectra gradually decrease with adding more Fe3O4 NPs. The unit mass of the pure europium complex in some composite microfibers gave stronger luminescence than the pure europium complex. The fluorescence lifetime of 5D0 state in the composite microfibers is longer than that of pure europium complex. Additionally, the magnetic properties of Fe3O4 NPs and the composite microfibers were investigated. Fe3O4 NPs and composite microfibers were both superparamagnetic. The saturation magnetization of the composite microfibers was smaller than that of pure Fe3O4 NPs.

scholarly journals Synthesis of gold nanoparticles using Platycodon grandiflorum extract and its antipathogenic activity under optimal conditions

2020 ◽  
Vol 10 ◽  
pp. 184798042096169
Author(s):  
Periasamy Anbu ◽  
Subash CB Gopinath ◽  
S Jayanthi
Keyword(s):  
Electron Microscopy ◽  
Gold Nanoparticles ◽  
Plant Extracts ◽  
Photoelectron Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Platycodon Grandiflorum ◽  
Transmission Electron ◽  
Flower Plant ◽  
Average Size

Gold nanoparticles have many applications in the biomedical field, mainly for drug delivery, cancer therapy, and detection of pathogenic microorganisms. In this study, gold nanoparticles synthesized using Platycodon grandiflorum (Balloon flower plant) extracts were evaluated for their antibacterial potential. Gold nanoparticles were synthesized at 20–50°C using different volumes of the leaf extract. Biosynthesis of gold nanoparticles was confirmed by ultraviolet–visible spectral absorption at 545 nm by surface plasmon resonance. The morphology and size of the P. grandiflorum gold nanoparticles were further characterized as spherical in shape with an average size of 15 nm in diameter by scanning electron microscopy and transmission electron microscopy. Energy-dispersive X-ray analysis clearly displayed the presence of gold particles. The structural analysis results with face central cubic crystalline nature and elemental composition, including gold, were confirmed by X-ray diffraction and X-ray photoelectron spectroscopy, respectively. In addition, Fourier transform infrared results identified the functional group in P. grandiflorum that is involved in the reduction of metal ions to gold nanoparticles. The synthesized P. grandiflorum gold nanoparticles exhibited efficient antibacterial activity against Escherichia coli (16 mm) and Bacillus subtilis (11 mm). This report confirms the synthesis of gold nanoparticle from balloon flower plant extracts, which can be used as a reducing and stabilizing agent and demonstrates its antibacterial applications.

scholarly journals Comparing study of CuO synthesized by biological and electrochemical methods for biological activity

2019 ◽  
Vol 30 (1) ◽  
pp. 94 ◽  
Author(s):  
Shaimaa Hamed Jaber
Keyword(s):  
Electron Microscopy ◽  
Copper Oxide ◽  
Electrochemical Method ◽  
Cuo Nanoparticles ◽  
Biological Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Average Size ◽  
Cuo Nanoparticle

In the present work, copper oxide (CuO) nanoparticles have been synthesized by two methods (electro chemical and biological method).The synthesized nanoparticles characterized by x-ray diffraction (XRD), Scanning Electron Microscopy(SEM) and transmission Electron Microscopy(TEM). results show that to copper oxide (CuO) nanoparticle have average size of (11-15)nm of electrochemical method and (6-12 ) nm of biological method by different technique CuO nanoparticles were applied to study the inhibition of bacterial using (staphylococcus and pseudomonas). The antibacterial activity of CuO nanoparticles show a higher inhibition of pseudomonas bacteria when a compared with staphylococcus bacteria.

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