Design and Characterization of Ag@Cu2O-rGO Nanocomposite for the p-Nitrophenol Reduction

In this paper, we designed Ag nanoparticles coated with a Cu2O shell, which was successfully decorated on reduced graphene oxide (rGO) via a solid-state self-reduction. The Cu2O, Ag@Cu2O, and Ag@Cu2O-rGO nanocomposites were synthesized and characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis, and XPS to evaluate the properties of the composites. In order to compare the chemical catalytic activity, the Cu2O, Ag@Cu2O, and Ag@Cu2O-rGO nanocomposites were employed for the catalytic reduction of p-nitrophenol (4-NP) into p-aminophenol (4-AP) in aqueous solution. The Ag@Cu2O-rGO nanocomposite exhibited excellent catalytic activity due to the intense interaction and high degree of electron transfer among Ag, Cu2O, and rGO. The rGO acted as the platform to bridge the isolated nanoparticles; furthermore, the electrons could quickly transfer from the Ag core to the Cu2O shell, which improved the chemical catalytic efficiency.

Download Full-text

Fabrication and characterization of highly textured (Bi,Pb)2Sr2Ca2Cu3Ox superconducting ceramics using high magnetic field and cold isostatic pressing

Journal of Materials Research ◽

10.1557/jmr.1995.2433 ◽

1995 ◽

Vol 10 (10) ◽

pp. 2433-2443 ◽

Cited By ~ 4

Author(s):

Wai Lo ◽

R. Stevens ◽

R. Doyle ◽

A.M. Campbell ◽

W.Y. Liang

Keyword(s):

Magnetic Field ◽

Electron Microscopy ◽

Cold Isostatic Pressing ◽

Sintered Ceramic ◽

Grain Alignment ◽

Isostatic Pressing ◽

Transmission Electron ◽

Superconducting Ceramics ◽

High Degree

High textured (Bi,Pb)2Sr2Ca2Cu3Ox ceramics have been fabricated by aligning deflocculated flakes of (Bi,Pb)2Sr2Ca2Cu3Ox suspended in an organic medium by means of a high de magnetic field (6 T) at room temperature followed by cold isostatic pressing. The proportion of the (Bi,Pb)2Sr2Ca2Cu3Ox phase in the precursor powder was carefully controlled, and the characteristics of the powder, such as size distribution and morphology, were determined. A high degree of grain alignment was found in the specimens after the magnetic alignment, although the bulk density of the materials was low. Cold isostatic pressing substantially increased the density of the magnetically prealigned specimens which also resulted in a slight decrease in the degree of grain alignment. This minor realignment was found to be due to the various kinds of processing defects that appeared in the specimens during compaction due to the grinding and cracking of the grains and their interlocking. The microstructural and superconducting properties of the sintered ceramic have been studied using texture goniometry, high resolution scanning electron microscopy, transmission electron microscopy, ac magnetic susceptometry, and critical current measurements.

Download Full-text

Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.508 ◽

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.

Download Full-text

Characterization of Al65.0Cu32.9Co2.1 Alloy Containing Nanofibres

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.186.212 ◽

2012 ◽

Vol 186 ◽

pp. 212-215

Author(s):

Jacek Krawczyk ◽

Włodzimierz Bogdanowicz ◽

Grzegorz Dercz ◽

Wojciech Gurdziel

Keyword(s):

Electron Microscopy ◽

Average Diameter ◽

Chemical Compositions ◽

X Ray ◽

Transmission Electron ◽

Orthogonal Set ◽

T Phase ◽

Terminal Area ◽

Scanning Electron

Microstructure of terminal area of Al65Cu32.9Co2.1ingots (numbers indicate at.%), obtained via directional solidification was studied. Scanning Electron Microscopy, Transmission Electron Microscopy and X-ray powder diffraction were applied. Point microanalysis by Scanning Electron Microscope was used for examination of chemical compositions of alloy phases. It was found that tetragonal θ phase of Al2Cu stoichiometric formula was the dominate phase (matrix). Additionally the alloy contained orthogonal set of nanofibres of Al7Cu2Co T phase with the average diameter of 50-500 nm and oval areas of hexagonal Al3(Cu,Co)2H-phase, surrounded by monoclinic AlCu η1phase rim. Inside some areas of H-phase cores of decagonal quasicrystalline D phase were observed.

Download Full-text

Synthesis and characterization of homogeneous lead-substituted tin oxide with the (110) face of rutile structure

Journal of Materials Research ◽

10.1557/jmr.2000.0298 ◽

2000 ◽

Vol 15 (10) ◽

pp. 2076-2079

Author(s):

Chika Nozaki ◽

Takashi Yamada ◽

Kenji Tabata ◽

Eiji Suzuki

Keyword(s):

Electron Microscopy ◽

Tin Oxide ◽

Photoelectron Spectroscopy ◽

Synthesis And Characterization ◽

X Ray Diffraction ◽

Rutile Structure ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Synthesis of a rutile-type lead-substituted tin oxide with (110) face was investigated. The characterization was performed by x-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, infrared spectroscopy, x-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The homogeneous rutile-type lead-substituted tin oxide was obtained until 4.1 mol% of tin was substituted with lead. The surface of obtained oxide had a homogeneously lead-substituted (110) face.

Download Full-text

Reduced Graphene Oxide–Epoxy Grafted Poly(Styrene-Co-Acrylate) Composites for Corrosion Protection of Mild Steel

Coatings ◽

10.3390/coatings9100666 ◽

2019 ◽

Vol 9 (10) ◽

pp. 666

Author(s):

Xinchuan Fan ◽

Yue Hu ◽

Yijun Zhang ◽

Jiachen Lu ◽

Xiaofeng Chen ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Corrosion Properties ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Scanning Electron

Reduced graphene oxide–epoxy grafted poly(styrene-co-acrylate) composites (GESA) were prepared by anchoring different amount of epoxy modified poly(styrene-co-acrylate) (EPSA) onto reduced graphene oxide (rGO) sheets through π–π electrostatic attraction. The GESA composites were characterized by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The anti-corrosion properties of rGO/EPSA composites were evaluated by electro-chemical impedance spectroscopy (EIS) in hydroxyl-polyacrylate coating, and the results revealed that the corrosion rate was decreased from 3.509 × 10−1 to 1.394 × 10−6 mm/a.

Download Full-text

Synthesis and Characterization of Novel AlF3 Cubes

NANO ◽

10.1142/s179329201550071x ◽

2015 ◽

Vol 10 (05) ◽

pp. 1550071 ◽

Cited By ~ 1

Author(s):

Maoquan Xue ◽

Changsheng Li

Keyword(s):

Electron Microscopy ◽

Synthesis And Characterization ◽

Metal Fluoride ◽

Controlled Synthesis ◽

X Ray ◽

Transmission Electron ◽

Cubic Structure ◽

Synthesis Approach ◽

Scanning Electron

In this paper, regularly shaped AlF 3 particles with cubic structure were successfully synthesized via a solvothermal route. The as-prepared products were characterized by X-ray powder diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The experimental results indicated that reaction temperature and time have significant effects on the morphology of the as-prepared products. A possible formation process has also been investigated on the basis of a series of XRD and SEM studies of the product obtained at different conditions. This well-controlled synthesis approach may be extended to fabricate other metal fluoride materials.

Download Full-text

Structural characterization of Yba2Cu3O7–δ/Y2O3 composite films

Journal of Materials Research ◽

10.1557/jmr.1998.0133 ◽

1998 ◽

Vol 13 (4) ◽

pp. 954-958 ◽

Cited By ~ 3

Author(s):

P. R. Broussard ◽

M. A. Wall ◽

J. Talvacchio

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Coincidence Site Lattice ◽

Composite Films ◽

X Ray Diffraction ◽

Plane Orientation ◽

Transmission Electron ◽

Two Phases ◽

High Degree

Using 4-circle x-ray diffraction and transmission electron microscopy, we have studied the microstructure and in-plane orientation of the phases present in thin film composite mixtures of Yba2Cu3O7–δ and Y2O3. We see a high degree of in-plane orientation and have verified a previous prediction for the in-plane order of Y2BaCuO5 on (110) MgO. Transmission electron microscopy shows the composite films to be a mixture of two phases, with YBCO grain sizes of ≈1 μm. We have also compared our observations of the in-plane order to the predictions of a modified near coincidence site lattice model.

Download Full-text

Preparation and Characterization of Nanostructured Hollow MgO Spheres

Materials ◽

10.3390/ma12030537 ◽

2019 ◽

Vol 12 (3) ◽

pp. 537

Author(s):

Jishuo Han ◽

Guohua Li ◽

Lin Yuan

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Shell Thickness ◽

Template Method ◽

X Ray Diffraction ◽

X Ray ◽

Carbon Microsphere ◽

Transmission Electron ◽

Scanning Electron

Nanostructured hollow MgO microspheres were prepared by the template method. First, D-Anhydrous glucose was polymerized by the hydrothermal method to form a template. Second, a colorless solution was obtained by mixing magnesite with hydrochloric acid in a 1:2 proportion and heating in an 80 °C water bath for 2 h. Finally, the template from the first step was placed in the colorless solution, and the resulting precipitate was calcined at 550 °C for 2 h. The phase composition and microstructure of the calcined samples were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD results indicated that the main crystal is periclase. The SEM results indicates that the template carbon microsphere surface is smooth, and the its size is uniform and concentrated in the range of 100–200 nm. The diameters of the samples range from 60 to 90 nm, which is smaller than the size of the carbon microsphere. The TEM results indicates that the sample is hollow with a shell thickness of about 6–10 nm. The specific surface area of the calcined hollow sphere is 59.5 m²·g−1.

Download Full-text

Characterization of monoclonal IgG cryoglobulins: fine-structural and morphological analysis

Blood ◽

10.1182/blood.v69.2.677.677 ◽

1987 ◽

Vol 69 (2) ◽

pp. 677-681 ◽

Cited By ~ 12

Author(s):

DN Podell ◽

CH Packman ◽

J Maniloff ◽

GN Abraham

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Morphological Analysis ◽

Vascular Occlusion ◽

Molecular Clusters ◽

Morphological Properties ◽

Transmission Electron ◽

Thin Walled ◽

Scanning Electron

Abstract The morphology of the amorphous, gelatinous, and crystalline varieties of monoclonal IgG cryoglobulins was analyzed by light and transmission and scanning electron microscopy. Each cryoglobulin had a characteristic fine structure that correlated with its gross morphology. Transmission electron microscopy showed that the amorphous precipitates were random and disorganized molecular clumps. In contrast, cryogels were thin-walled, well-organized, and hydrated strawlike clusters, whereas cryocrystals formed tightly compacted, highly structured molecular clusters. Crystals that formed in blood produced rouleaux, and analysis by scanning electron microscopy indicated that the crystals could form thick-walled, branching, macromolecular nets that could physically trap cells. The morphological properties provided visual impressions by which cryoglobulins could cause clinical disease secondary to vascular occlusion produced by self- associated IgG cryoglobulin molecules.

Download Full-text