Functionalization of Multi Wall Carbon Nanotubes Using Nitric Acid Oxidation

Abstract

Functionalized of Multi Wall Carbon Nanotubes (MWCNTs) were demonstrated using the nitric acid (HNO3) oxidation technique in order to get opened caps, removing carbonaceous and metal particles impurities for carboxylic groups (-COOH). The surface morphology and the existence of the carboxyl-group on the MWCNTs were examined using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM), respectively. The carboxylic groups were observed at the peak of 1640.40cm-1via FTIR and indicate the absorbance intensity of the functionalized MWCNTs is 2.22 A which is higher than raw material. Furthermore, SEM image shows the bundle of structure on the raw MWCNTs signified the Van der Waals interaction between MWCNTs while after functionalized a groovy CNTs wall were observed due to presence of carboxyl group at the defect sites.

Selective carboxylation versus layer-by-layer unsheathing of multi-walled carbon nanotubes: new insights from the reaction with boiling nitrating mixture

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Highly stable binder free CNTs/rGO aerogel electrode for decolouration of methylene blue & palm oil mill effluent via electro-Fenton oxidation process

“…The presence of CNTs helps in increasing the surface area and active sites. 24,32 Due to the high roughness and porosity of the aerogel surfaces, bulk resistance was measured instead of sheet resistance. Bulk resistance of the rGO aerogel was decreased from approximately 20 kU to 40 and 18 U with the addition of 30% and 60% CNTs, respectively.…”

Electrochemical Detection of Ascorbic Acid in Oranges at MWCNT-AONP Nanocomposite Fabricated Electrode

“…The mixture was then filtered with deionized water until a pH 7 was reached. The finished product was dried in an oven overnight [56].…”