Effect of Time on the Syntheses of Carbon Nanotubes via Domestic Oven

N Kure,N M Hamidon,B U Machu,I H Daniel,I I Lakin,E J Adoyi

doi:10.46481/jnsps.2022.355

Abstract

In this study, carbon nanotubes (CNTs) were synthesized directly on coated silicon substrate via commercial microwave oven at 2.45 GHzf for3 minutes (Sample A) and 4 minutes (Sample B). The plasma provides the required temperature for catalytic decomposition of carbon source (polyethylene) at 750 ?C under atmospheric pressure. Raman spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscope (HRTEM), X-ray diffractometer (XRD) techniques are used to characterize the as-synthesized. Results indicate that, the calculated carbon quality was found to be 1.01 and 1.02 for sample A and sample B respectively with average diameter range of (6.0 to 10.0) ± 0.5 nm. The high intensity ratio is attributed to the defect mode in the CNTs. Also, the analysis from FESEM shows twisted and randomly oriented structures with an interlayer spacing of about 0.35 nm in the internal structure of most CNTs. HRTEM further confirmed the interlayer spacing of about 0.35 nm corresponding to FESEM result. The crystallinity of the CNTs was obtained via X-ray diffraction techniques. Lastly, the results indicate sample A and B produces CNTs, with sample B having more graphitic structure than sample A due to duration of synthesis process.

Highlights

Carbon nanotubes (CNTs) are carbon-based nanomaterials which has attracted much interest from scientific community due to its exceptional carbon-carbon bonding which assists carbon to form its allotropes, such include carbon nanofibers; graphites; graphenes and carbon quantum dots [1, 2, 3, 4, 5]
The CNTs diameters are in comparison with related works and it is believed that the catalyst particle size has significant effect on the CNTs diameter due to interaction between the catalyst and the substrate [4, 17]
The synthesis pressure and temperature were maintained at 0.81 mbar and 750 ◦C respectively and the reaction was carried out for a period of 3 minutes and 4 minutes for sample A and sample B respectively

Summary

Introduction

Carbon nanotubes (CNTs) are carbon-based nanomaterials which has attracted much interest from scientific community due to its exceptional carbon-carbon bonding which assists carbon to form its allotropes, such include carbon nanofibers; graphites; graphenes and carbon quantum dots [1, 2, 3, 4, 5] These exceptional properties possess by the nanomaterials tremendously revolutionize the area of carbon-based nanoscience such as electrical, thermal, chemical and mechanical properties [1, 6]. Researchers developed keen interest on how to synthesize this carbon-based nanomaterial among such methods are arc discharge [6], laser ablation [10] and chemical vapor deposition [11] These techniques of synthesizing CNTs are believed to be time consuming and expensive, in order to eliminate that, an attempt was made in this study to synthesize CNTs on silicon substrate using commercial microwave oven with operating power of 600 W at 2.45 GHz utilizing the microwave energy [4, 12].

Methods

Results

Conclusion