Poly(Diphenylamine) with Multi-walled Carbon Nanotube Composite Film Modified Electrode for the Determination of Phenol

Abstract

In this study I report the electrochemical oxidation of phenol at a poly diphenylamine (PDPA)- multi- walled carbon nanotube (MWCNT) composite film modified glassy carbon electrode (GCE). PDPA was polymerized on the MWCNT modified GCE by cyclic voltammetry (CV) in 0.1 M H2SO4. The surface morphology of PDPA-MWCNT was studied using scanning electron microscope (SEM). The interfacial electron transfer phenomenon at the modified electrode was studied using electrochemical impedance spectroscopy (EIS). The PDPA-MWCNT composite film showed good electrocatalytic behavior towards the oxidation of phenol in pH 7. Phenol showed a well defined anodic peak at 0.65 V (vs. Ag/AgCl electrode). The MWCNT in PDPA-MWCNT film enhanced the anodic peak current by 8.48 and 2.36 times than that of MWCNT/GCE and PDPA/GCE electrode. The peak current increased linearly with phenol concentration. The amperometric determination of phenol at the composite film modified electrode showed linear range from 9.8 to 80 μM. This result shows that the proposed composite electrode may be developed for potential application in real sample analysis.