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Updated: Oct 2, 2025
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Published on: April 15, 2013
Electro-oxidation of amino-functionalized multiwalled carbon nanotubes
Yuanyuan Lu1, Xiuting Li2, Richard G Compton1
1Department of Chemistry, Physical and Theoretical Chemistry Laboratory, Oxford University South Parks Road Oxford OX1 3QZ UK richard.compton@chem.ox.ac.uk.
Abstract:
We report the electrochemistry of amino-functionalized multiwalled carbon nanotubes (MWCNTs-NH2) in the pH range from 0.3 to 6.4 using quantitative cyclic voltammetry (CV) and single entity electrochemistry measurements, making comparison with non-functionalized MWCNTs. CV showed the latter to both catalyze the solvent (water) decomposition and to undergo irreversible electro-oxidation forming oxygen containing surface functionality. The MWCNTs-NH2 additionally undergo an irreversible oxidation to an extent which is dependent on the pH of the solution, reflecting the variable amount of deprotonated amino groups present as a function of pH. Nano-impact experiments conducted at the single particle level confirmed the oxidation of both types of MWCNTs, showing agreement with the CV. The pK a of the amino groups in MWCNTs was determined via both electrochemical methods giving consistent values of ca. 2.5.
