Study on electrochemical behavior of ortho-aminophenol on nano-gold/carbon nanotubes composite modified electrode

摘要

The aim of this work was to construct a novel modified electrode based on Au nano-particles and carbon nanotube for studying 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 coefficient (D) could be estimated and the result was 5.42×10~(-7) cm ~2·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.