[01] Oluwasina Oludayo Olugbenga, Department of Chemistry, Federal University of Technology, Akure, Ondo State, Nigeria; Department of Chemical, University of the Witwatersrand, Johannesburg, South Africa. [02] Daramola Olawale Michael, Department of Chemical, University of the Witwatersrand, Johannesburg, South Africa. [03] Iyuke Sunny, Department of Chemical, University of the Witwatersrand, Johannesburg, South Africa.

Weight loss and surface defects are side effects of Carbon nanotubes (CNTs) purification and functionalization with mineral acids. The potential of using 3:1 concentrated acetic acid: hydrochloric acid was investigated in order to purify and functionalize CNTs. Multi-walled carbon nanotubes were analyzed by TEM, TGA, Raman, FTIR, and XRD. The XRD patterns indicated the preservation of the crystalline nature of MWCNTs after the purification and functionalization. There was improvement in the purity of the CNTs as shown in the TEM morphology of pCNTs and fCNTs. The Raman spectroscopy analysis showed that there was an increase in the (I_D/I_G) of functionalized MWCNTs to 0.85 from 0.84 of the pCNTs, indicating introduction of functional groups to the carbon surface. The TGA curve indicated that the aCNTs was most thermally stable than both the pCNTs and fCNTs. There was also an indication of increase in hydrophilicity of the fCNTs due to the functionalization. The functionalization of the CNTs was confirmed in the FTIR spectra of the material. The results obtained demonstrated the potential of using organic acid – inorganic acid mixture for the purification of CNTs for the preservation of structure and morphology of the CNTs with possible functionalization.

Carbon Nanotubes, Purification, Functionalization, Characterization, Organic-Inorganic Acid

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