Mechanism of vertically arrays of carbon nanotubes by camphor based catalysed in-situ growth

Abstract

In this study, a growth mechanism of vertically aligned carbon nanotubes (VACNT) on a nanostructured porous silicon template (NPSiT) was proposed based on the experimental observations obtained. Camphor oil and ferrocene (Fe) were used as a carbon source and a catalyst, respectively. The NPSiT was optimised and used as a template to synthesise VACNT. The VACNT was synthesised on NPSiT by using a double thermal chemical vapour deposition (DTCVD) method. The synthesis was also performed via a floated method in a DTCVD reactor by using an in-situ catalyst in the absence of any catalysts pre-treatment. Each of the growth mechanisms was proposed based on the TEM images obtained at different synthesis conditions. From the results, a mixed top and bottom growth model was proposed for the growth mechanism of VACNT at the pores and pillars. On the contrary, the tip growth model was proposed for the growth inside the pores, while the valley growth model was proposed for the growth within the pillars of NPSiT. Furthermore, a mixed tip and valley growth model was proposed based on the location of Fe particles.

GRAPHICAL ABSTRACT

Keywords:

• Carbon nanotubes
• vertically aligned carbon nanotubes
• porous silicon
• growth mechanism
• tip growth
• bottom growth

Acknowledgments

The authors would like to express our greatest gratitude to Ministry of Higher Education Malaysia for FRGS Grant Scheme (600-IRMI/FRGS/5/3(415/2019)), Research Management Centre (RMC) Universiti Teknologi MARA, Functional Materials and Nanotechnology Centre, Institute of Science (IOS) and Faculty of Applied Sciences, Universiti Teknologi MARA for the support. This project under grant number 600-IRMI/FRGS/5/3(415/2019).

Disclosure statement

On behalf of all authors, the corresponding author states that there is no conflict of interest.