The aim of this work was to construct a novel modified electrode based on Au nano-particles and carbon nanotube for study- ing the electrochemical behavior of ortho-aminophenol (OAP). A sensitive oxidation peak of OAP at the potential of 0.352V was observed in HAc-NaAc-PHP buffer solution. The effect factors of the electrochemical response of OAP were optimized by linear sweep voltammetry (LSV). Under the optimum conditions, a linear calibration curve of the peak current of OAP and concentration was obtained in the range of 4.0×10-7~2.0×10-4 mol/L. The oxidation peak current increases direct proportionally with the square root of scanning speed, which indicates that the electrochemical oxidation process of OAP on this modified electrode is diffusion-controlled process. The diffusion coeffi- cient (D) could be estimated and the result was 5.42×10-7 cm2·s-1 by employing chronocoulometry. The charge transfer rate constant (ks) was also discussed and the result was 7.85×10-4 cm·s-1. Concurrently, based on the experiment results, the electrode reaction process of OAP with one electron and one proton was proposed.
Ortho-aminophenol; Au nano-particles; Multi-walled carbon nanotube; Au electrode; Voltammetry
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