Synthesis and Optimization of MWCNTs on Co-Ni/MgO by Thermal CVD

H Ryu,K S Bartwal,B K Singh

doi:10.1155/2008/971457

Abstract

Multiwalled carbon nanotubes (MWCNTs) were prepared by the thermal chemical vapor deposition (CVD) technique. Monometallic and bimetallic Co and Ni combinations were used as a catalyst on MgO support. The mixer ofH2/C2H2was used as a carbon source. The prepared CNTs were found to possess different shapes, morphologies, and sizes. Maximum yield was found for 50% Co (MgO: 50% and Ni: 0%) catalyst at 600°C. Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques were used for structural analysis. Raman spectra were taken to investigate the quality and crystalline perfection of the prepared CNTs. The ratio of D- and G-bands (ID/IG) was measured from these spectra.

Highlights

Carbon nanotubes (CNTs), discovered in 1992 by Iijima [1], are tiny, hollow tubes made of pure carbon just a few nanometers in diameter and up to few hundreds microns in length
We report results on optimization of Co- and Nibased monometallic and bimetallic catalytic systems for the synthesis of multiwalled carbon nanotubes (MWNT) by decomposition of acetylene (C2H2)
Carbon nanotubes were prepared by thermal chemical vapor deposition method using Co/Ni as catalyst and C2H2 as a carbon source

Summary

Introduction

Carbon nanotubes (CNTs), discovered in 1992 by Iijima [1], are tiny, hollow tubes made of pure carbon just a few nanometers in diameter and up to few hundreds microns in length. Carbon nanotubes exhibit unique electrical properties, efficient heat conductivity, and excellent mechanical strength. Due to their outstanding physical properties, CNTs are one of nanotech’s most promising molecular building blocks. The current density in CNTs can be a factor of 102–103 higher than in metals. Nanostructured graphitic materials such as single-wall carbon nanotubes (SWNT) and multiwalled carbon nanotubes (MWNT) [5], fullerenes, onion-like carbon, and related structures [6] are mainly obtained by evaporating solid carbon targets by means of arc-discharge and laser ablation. We correlate the morphology and structural features with the employed catalytic combination

Experimental Details

Results and Discussion

Conclusion