Formation and characterization of catalytic carbons obtained from co disproportionation over an iron nickel catalyst—II

Supported Rh nanoparticles obtained by reduction in hydrogen of severely calcined Rh/Mg/Al hydrotalcite-type (HT) phases have been characterized by FT-IR spectroscopy of adsorbed CO [both at room temperature (r.t.) and nominal liquid nitrogen temperature] and Transmission Electron Microscopy (TEM). The effect of reducing temperature has been investigated, showing that Rh crystal size increases from 1.4 nm to 1.8 nm when the reduction temperature increases from 750°C to 950°C. The crystal growth favours the formation of bridged CO species and linear monocarbonyl species with respect to gem-dicarbonyl species; when CO adsorbs at r.t., CO disproportionation occurs on Rh and it accompanies the formation of RhI(CO)2. The role of interlayer anions in the HT precursors to affect the properties of the final materials has been also investigated considering samples prepared from silicate-instead of carbonate-containing precursors. In this case, formation of RhI(CO)2 and CO disproportionation do not occur, and this evidence is discussed in terms of support effect.

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Synthesis and Characterization of Exotic Carbon Fibers with Branched Spurs Using Nickel Catalyst Precursor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.645.3 ◽

2013 ◽

Vol 645 ◽

pp. 3-9

Author(s):

Qian Zhang ◽

Qiu Xiang Wang ◽

Hong Zhou Dong ◽

Li Feng Dong

Keyword(s):

Electron Microscopy ◽

Nickel Catalyst ◽

Carbon Fibers ◽

Vapor Deposition ◽

Chemical Vapor ◽

Chemical Vapor Deposition Method ◽

Catalyst Precursor ◽

X Ray ◽

Transmission Electron

In this paper, we have synt hesized exotic carbon fibers with branched spurs by a chemical vapor deposition method using nickel catalyst precursor at 600 °C. No catalyst particles were found at the base of the carbon spurs, suggesting that the ni ckel catalyst particles, which were decomposed from the nickel catalyst precursor, facilitated the growth of the carbon fibers but not the spurs. The formation of the spurs resulted from the fluctuation of the carbon source gas acetylene flow. The samples were characterized by field emission sc anning electron microscopy, transmission electron microscopy, and X-ray powder diffraction.

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Multi-Length Scale Characterization of the Gibeon Meteorite using Electron Backscatter Diffraction

Microscopy Today ◽

10.1017/s1551929500061162 ◽

2007 ◽

Vol 15 (5) ◽

pp. 6-11 ◽

Cited By ~ 1

Author(s):

Matthew M. Nowell ◽

John O. Carpenter

Keyword(s):

Electron Backscatter Diffraction ◽

Nickel Content ◽

Iron Core ◽

Face Centered Cubic ◽

Iron Nickel ◽

Scale Characterization ◽

Face Centered ◽

Two Phases ◽

Backscatter Diffraction

The Gibeon meteorite is a differentiated iron meteorite that fell in Nambia, Africa in prehistoric times, with fragments spread over an area 70 miles wide and 230 miles long. The Gibeon fall was initially discovered in 1836, and hundreds of thousands of kilograms of fragments have been recovered. These fragments represent the iron core of a meteorite that cooled and crystallized over thousands of years (Norton 2002).The microstructure of the Gibeon meteorite, which is primarily an iron-nickel alloy, consists of two phases: kamacite, a body-centered cubic material and taenite, a face-centered cubic material that metallurgists would refer to as ferrite and austenite respectively. This material initially crystallizes as taenite, and as the temperature decreases, transforms into kamacite. This meteorite is classified as a Fine Octahedrite (Of) with an average Nickel content of approximately 7.9%

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Synthesis and characterization of MWNTs with narrow diameter over nickel catalyst by MPCVD

Scripta Materialia ◽

10.1016/s1359-6462(02)00445-1 ◽

2003 ◽

Vol 48 (4) ◽

pp. 409-412 ◽

Cited By ~ 23

Author(s):

S Wang

Keyword(s):

Nickel Catalyst ◽

Synthesis And Characterization

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Characterization of Single-Walled Carbon Nanotubes (SWNTs) Produced by CO Disproportionation on Co−Mo Catalysts

Chemistry of Materials ◽

10.1021/cm011613t ◽

2002 ◽

Vol 14 (4) ◽

pp. 1853-1858 ◽

Cited By ~ 118

Author(s):

W. E. Alvarez ◽

F. Pompeo ◽

J. E. Herrera ◽

L. Balzano ◽

D. E. Resasco

Keyword(s):

Carbon Nanotubes ◽

Single Walled Carbon Nanotubes ◽

Single Walled Carbon ◽

Co Disproportionation ◽

Walled Carbon Nanotubes

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Purification and characterization of an iron-nickel hydrogenase from Thermococcus celer

JBIC Journal of Biological Inorganic Chemistry ◽

10.1007/s007750100222 ◽

2001 ◽

Vol 6 (5-6) ◽

pp. 517-522 ◽

Cited By ~ 3

Author(s):

Jenny M. Blamey ◽

Mario Chiong ◽

Eugene T. Smith

Keyword(s):

Purification And Characterization ◽

Iron Nickel ◽

Thermococcus Celer

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Synthesis and Characterization of Calcium Hexaboride (CaB6) Nanowires

The Journal of Undergraduate Research at the University of Illinois at Chicago ◽

10.5210/jur.v1i1.7448 ◽

2007 ◽

Vol 1 (1) ◽

Author(s):

S Tan ◽

P. Jash ◽

M. Trenary

Keyword(s):

Nickel Catalyst ◽

Gas Flow ◽

Synthesis Method ◽

Reaction Chamber ◽

Tem Analysis ◽

Calcium Hexaboride ◽

Edx Analyses ◽

Boron Nanowires ◽

Quartz Tube Furnace

The objective of the current research was to synthesize calcium hexaboride (CaB6) nanowires for analysis of hydrogen storage materials. Catalyst assisted growth of nanowires under the Vapor-Liquid-Solid synthesis method was performed in a quartz tube furnace. The pyrolysis of diborane (B2H6) gas over calcium oxide (CaO) powders with a thermally coated layer of nickel catalyst was carried out. SEM and TEM analysis have shown the generation of nanowires although calcium and boron did not react in a 1:6 ratio, though 1:4 and 1:8 ratios were achieved. Several types of nanowire compositions were found under EELS and EDX analyses, including calcium and oxygen coated boron nanowires. Overall, it was found that a decrease in the amount of nickel catalyst used is correlated to a decrease in the diameters of the nanowires. A higher diborane gas flow rate into the reaction chamber was also correlated to more abundant nanostructures in the sample.

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