Hydrogen adsorption in single-walled and multi-walled carbon nanotubes grown in a hot-wire CVD (Cat-CVD) reactor

ABSTRACTMultiwalled carbon nanotubes (MWNTs) were continuously synthesized by hot wire chemical vapor deposition (HWCVD) using a methane source catalyzed by metal-organic ferrocene. The microstructure of the MWNTs and the catalyst particles were subsequently characterized with transmission electron microscopy which identified three different phases, i.e., bcc α-Fe, fcc γ-Fe and orthorhombic Fe3C. The hydrogen storage capacity of MWNTs was determined with temperature-programmed desorption (TPD) technique. Hydrogen adsorption at near ambient conditions was observed only in as-synthesized MWNTs containing iron particles and was dramatically increased after hydrogen reducing treatment. Possible adsorption mechanism was also discussed.

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Study of electron field emission from arrays of multi-walled carbon nanotubes synthesized by hot-wire dc plasma-enhanced chemical vapor deposition

Journal of Non-Crystalline Solids ◽

10.1016/j.jnoncrysol.2006.01.065 ◽

2006 ◽

Vol 352 (9-20) ◽

pp. 1352-1356 ◽

Cited By ~ 8

Author(s):

Costel Sorin Cojocaru ◽

Dohyung Kim ◽

Didier Pribat ◽

Jean-Eric Bourée ◽

Eric Minoux ◽

...

Keyword(s):

Carbon Nanotubes ◽

Chemical Vapor Deposition ◽

Field Emission ◽

Vapor Deposition ◽

Chemical Vapor ◽

Electron Field Emission ◽

Hot Wire ◽

Multi Walled Carbon Nanotubes ◽

Electron Field ◽

Walled Carbon Nanotubes

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Synthesis of multi-walled carbon nanotubes in high yield using Mm based AB2alloy hydride catalysts and the effect of purification on their hydrogen adsorption properties

Nanotechnology ◽

10.1088/0957-4484/16/4/031 ◽

2005 ◽

Vol 16 (4) ◽

pp. 518-524 ◽

Cited By ~ 25

Author(s):

M M Shaijumon ◽

N Rajalakshmi ◽

Hojin Ryu ◽

S Ramaprabhu

Keyword(s):

Carbon Nanotubes ◽

Hydrogen Adsorption ◽

Adsorption Properties ◽

High Yield ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

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Determination of the Isosteric Heat of Adsorption of Hydrogen on the Multi-Walled Carbon Nanotubes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.1484 ◽

2012 ◽

Vol 512-515 ◽

pp. 1484-1491 ◽

Cited By ~ 1

Author(s):

Qing Rong Zheng ◽

Shuai Gao ◽

Chen Jie

Keyword(s):

Carbon Nanotubes ◽

Hydrogen Adsorption ◽

Isosteric Heat ◽

Heat Of Adsorption ◽

Step Method ◽

Surface Loading ◽

Isosteric Heat Of Adsorption ◽

Hydrogen Molecules ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

The isosteric heat of adsorption was used to study the interaction between hydrogen molecules and the Multi-Walled Carbon Nanotubes (MWCNTs). Characterizations of the MWCNTs sample were carried out based on the N2 adsorption isotherm at 77 K and the images from TEM and HRTEM. Step by step method was used to volumetrically measure hydrogen adsorption isotherms at equilibrium temperature-pressures from 123-310 K and 0-12.3 MPa. Isosteric heats of adsorption at seven excess adsorption amounts and that at zero surface loading were respectively determined by the slopes of the adsorption isosteres and the plot of the temperature dependence of the Henry’s constants. Results show that the limit of the isosteric heat of adsorption at zero surface loading is about and the mean under the experimental condition is about . The values are in the same grade as those of hydrogen on the activated coconut charcoal but smaller than those of hydrogen on the graphitized carbon black P33, the activated carbon AX-21 and the Single-Walled Carbon Nanotubes (SWCNTs). Conclusions are drawn that relatively lower adsorption amounts and the isosteric heat of hydrogen adsorption on the MWCNTs could be ascribed to the small specific surface area and the large mesopores.

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