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Effect of reaction temperature in the selective synthesis of single wall carbon nanotubes (SWNT) on a bimetallic CoCr-MCM-41 catalyst

Paper ID Volume ID Publish Year Pages File Format Full-Text
42155 45912 2010 8 PDF Available
Title
Effect of reaction temperature in the selective synthesis of single wall carbon nanotubes (SWNT) on a bimetallic CoCr-MCM-41 catalyst
Abstract

Synthesis of single wall carbon nanotubes (SWNT) on a CoCr-MCM-41 bimetallic catalyst by CO disproportionation has been carried out at five different temperatures between 500 and 900 °C. A series of methods have been employed for a comprehensive assessment effect of temperature on the size-controllability of the catalyst particles and the morphology of the resultant SWNT. By extended fine structure X-ray absorption, thermogravimetric analysis, resonance Raman spectroscopy, photoluminescence excitation (PLE) mapping and transmission electron microscopy we found an optimal synthesis temperature window between 600 and 800 °C. In this window, modifying the reaction temperature leads to significant changes in the SWNT yield, diameter and chirality distribution. Decrease in reaction temperature favored the selective synthesis of very small diameter carbon nanotubes (as low as 0.6 nm). Chirality dependence of SWNT on temperature has been measured by PLE. A progressive suppression of larger diameter SWNT identities in the measured SWNT population was noted when reaction temperature decreased. In the measured PL maps, two near armchair structures (6,5) and (7,3) were dominant at 600 and 700 °C.

Graphical abstractA bimetallic CoCr-MCM-41 catalyst was used for production of SWNT by CO disproportionation. The effect of reaction temperature over the size-controllability of the catalyst particles and the morphology of the resultant SWNT was studied. Decrease in reaction temperature favored the selective synthesis of very small diameter nanotubes. Lower reaction temperature was favorable for the selective synthesis of certain tube identities.Figure optionsDownload full-size imageDownload high-quality image (165 K)Download as PowerPoint slide

Keywords
Carbon nanotubes; Diameter; Selectivity; Bimetallic; Catalyst; Cobalt; Chromium; Temperature
First Page Preview
Effect of reaction temperature in the selective synthesis of single wall carbon nanotubes (SWNT) on a bimetallic CoCr-MCM-41 catalyst
Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volume 374, Issues 1–2, 1 February 2010, Pages 213–220
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis