Single-Walled Carbon Nanotube Synthesis Yield Variation in a Horizontal Chemical Vapor Deposition Reactor.

Sung-Il Jo,Goo-Hwan Jeong

doi:10.3390/nano11123293

Abstract

The controlled synthesis of single-walled carbon nanotubes (SWNTs) is essential for their industrial application. This study investigates the synthesis yield of SWNTs, which depends on the positions of the samples on a horizontal chemical vapor deposition (CVD) system. Methane and Fe thin films were used as the feedstock and catalyst for SWNTs synthesis, respectively. A high-resolution scanning electron microscope was used to examine the synthesis yield variation of the SWNTs along the axial distance of the reactor. The morphology and crystallinity of the fabricated SWNTs were evaluated by atomic force microscopy and Raman spectroscopy, respectively. We observed that the highest synthesis yield of the SWNTs was obtained in the rear region of the horizontal reactor, and not the central region. These results can be applied to the synthesis of various low-dimensional nanomaterials, such as semiconducting nanowires and transition metal dichalcogenides, especially when a horizontal CVD chamber is used.

Highlights

Because the growth behavior of single-walled carbon nanotubes (SWNTs) is significantly influenced by the minute change in growth environment such as gas flow rate and growth temperature, we focused on the growth of SWNTs with respect to the sample position
The substrate installed at the rear region contained a higher amount of SWNTs than the central region, under all gas flow rate conditions
These results suggest that the actual thermal environment at the rear end of the chamber may have been higher than the chamber center because of a preheated gas flow from the central region, which is introduced with the appropriate gas speed

Summary

Introduction

We observed that the highest synthesis yield of the SWNTs was obtained in the rear region of the horizontal reactor, and not the central region. These results can be applied to the synthesis of various low-dimensional nanomaterials, such as semiconducting nanowires and transition metal dichalcogenides, especially when a horizontal CVD chamber is used. The specific growth of semiconducting or metallic SWNTs is highly desirable for device applications such as interconnections, electrodes, sensors, and other functional elements where superior electrical properties are required [2,3,4,5,6,7,8,9,10].

Methods

Results

Conclusion