Enhanced electrochemical growth and redox characteristics of poly(o-phenylenediamine) on a carbon nanotube modified glassy carbon electrode and its application in the electrocatalytic reduction of oxygen

The electrochemical growth current of poly(o-phenylenediamine) as well as its redox current were enhanced several-fold when deposited on a carbon nanotube modified glassy carbon electrode compared to the same at a glassy carbon surface. The current enhancements during the growth of the polymer were not due to any surface area effects but are attributed to a facilitated nucleation involving acidic sites of the carbon nanotube. The poly(o-phenylenediamine)-carbon nanotube composite electrode showed a polymer redox-mediated electrocatalytic effect for oxygen reduction reaction with a 5-fold enhancement in current and a favorable potential shift of 130 mV compared to the values obtained at a poly(o-phenylenediamine) electrode.