Dispersive Micro Raman Backscattering Spectroscopy Investigation of Arc Discharge Synthesized CNTs Doped by Boron and Nitrogen

Abstract

Raman scattering studies reveal the remarkable structure and the unusual electronic and phonon properties of carbon nanotubes. In this study, we directly produced boron, B, and nitrogen doped carbon nanotubes by using DC-arc discharge method which normally can be employed for producing carbon nanotubes. We performed experiments without using catalysts and in the presence of Ar gas for producing boron doped carbon nanotubes. At the second and third stages and in the presence of Al 2 O 3 and MgO nanopowders as catalysts and nitrogen gas were used for producing nitrogen doped carbon nanotubes. In general, our investigation revealed that some major changes caused by B and N dopants can be observed in the related recorded Raman spectra.

Efficient Coupling of Optical Energy for Rapid Catalyzed Nanomaterial Growth: High-Quality Carbon Nanotube Synthesis at Low Substrate Temperatures

“…The intensity of the 2D band increases and that of the D band decreases with increasing graphitization in the material, , therefore, their intensity ratio, I D / I 2D , is another metric of CNT quality; this is also supported by the similar trends observed in panels b and c in Figure . The low I D / I G ratios (0.67–0.44) and the presence of fully developed 2D bands in the Raman spectra given in Figure (a) indicate the high quality of as-grown CNTs, comparable with those grown by the arc-discharge method. , The measured growth rate in the present work has improved to 3.2 μm/min from 1.3 μm/min (when compared to our previous study, ref ) and there is a large improvement in the quality of CNTs grown in the current work as evident from the TEM and Raman spectroscopy. For example, the I D / I G ratio has reduced to 0.44 in the current work whereas it was 1.3 in the previous study.…”

“…24 The intensity of the indicate the high quality of as-grown CNTs, comparable with those grown by the arc-discharge method. 27,28 The measured growth rate in the present work has improved to 3.2 μm/min from 1.3 μm/min (when compared to our previous study, ref. 16) and there is a large improvement in the quality of CNTs grown in the current work as evident from the TEM and Raman spectroscopy.…”

“…The low I D /I G ratios (0.67−0.44) and the presence of fully developed 2D bands in the Raman spectra given in Figure 2(a) indicate the high quality of as-grown CNTs, comparable with those grown by the arc-discharge method. 27,28 The measured growth rate in the present work has improved to 3.2 μm/min from 1.3 μm/min (when compared to our previous study, ref 16) and there is a large improvement in the quality of CNTs grown in the current work as evident from the TEM and Raman This should be noted as CNT growth on metallic vs nonmetallic samples will be very different. The I D /I G ratio decreases from 0.66 to 0.44 (Figure 2a) as the CNT growth duration increases from 15 s to 20 min, whereas the corresponding increase in the temperature is only 19 °C (from 666 to 685 °C, see Figure 1b).…”

One-dimensional nitrogen-containing carbon nanostructures

“…NCNTs were rarely obtained by the arc-discharge of carbon electrodes in a N-containing gas atmosphere, e.g., helium/nitrogen atmosphere using iron-nickel-cobalt catalysts [34], and in a nitrogen atmosphere in the presence of Al 2 O 3 and MgO nanopowders as catalysts [35,36]. SWNCNTs were prepared using a quite different approach in an arc-discharge process [37,38], namely, instead of carrying out the experiment in a nitrogen rich atmosphere, nitrogen-rich organic precursor (melamine) was added into the graphite anode-rod.…”

In situ synthesis, structure, and properties of a dendritic branched nano‐thickening agent for high temperature fracturing fluid

“…Raman spectrum has been widely used to obtain the covalent attachment of the polymer onto the surface of MWCNTs . The Raman spectrum of nano‐thickening agent and MWCNTs were displayed in Figure .…”