Effect of Pt and Fe catalysts in the transformation of carbon black into carbon nanotubes

Abstract

a b s t r a c tIn this research carbon nanotubes and carbon nano onion-like structures were synthesized from carbon black using metal catalysts at 400°C and 700°C. Platinum and iron-group metals were used as catalysts for the transformation of CB into graphitized nanocarbon and the effect of both metals was compared. The synthesized products were characterized using X-ray diffraction (XRD), transmission electron microscope (TEM), high resolution transmission electron microscope (HRTEM) and Raman spectroscopy. The characterization shows that this process is very efficient in the synthesis of high quality graphitized products from amorphous carbon black, even though the process temperature was relatively low in comparison with previous studies. Distinguished graphitic walls of the newly formed carbon nanostructures were clearly visible in the HRTEM images. Possible growth difference related to the type of catalyst used is briefly explained with the basis of electron vacancies in d-orbitals of metals.

Characterization of carbon black modified by maleic acid

“…The measured graphene layer distance in CNX700 (0.33 nm) is very close to the interlayer distance for perfect graphite, 0.335 nm [138]. These findings are in agreement with both I D /I G values from Raman spectra of these samples shown above and also with the XRD analysis of the peaks in figure 1 of paper V [152].…”

“…shows an interlayer spacing d 002 around 3.66 [152]. The interlayer spacing of the samples CNPt, CNT700 and CNX700 is found to be closely related to the inter-planar distance in a graphitic structure (3.35Å) [138].…”

“…In this section, research works carried out for paper V [152] is discussed. The experiments were carried out at 700 °C with the samples prepared in a ceramic boat.…”

“…In this work, H 2 PtCl 6 was used as a source of Pt catalyst, with vitamin B 2 as a reducing agent. The basic principle of preparing such noble metal catalyst Reference [152].…”

“…The letter 'T' and 'X' denotes directly to the CB, Timcal 350G and XC72R, respectively. In the paper V [152], these samples are referred as CNT and CNX, respectively. The figures 5.6-5.9 are displayed below to get an overview of the samples CNPt, CNT700, CNX700 and CNG.…”