Electrochemical characterization of poly-beryllon II modified carbon paste electrode and its application to selective determination of pyrocatechol and hydroquinone.

ABSTRACT

A poly-beryllon II film modified carbon paste electrode (PBL-II/CPE) has been constructed by electropolymerization method. Electrochemical characterization of the PBL-II/CPE was investigated by electrochemical impedance spectroscopy (EIS). The electrochemical behaviors of pyrocatechol (PC) and hydroquinone (HQ) were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) at the PBL-II/CPE in pH 7.0 phosphate buffer solution (PBS). The anodic peak currents were dramatically enhanced about threefold for PC at PBL-II/CPE. In addition, the modified electrode exhibits good selectivity toward selective determination of PC and HQ. By using DPV method, low detection limits of 0.8µM for PC and 1.0µM for HQ were obtained, respectively. Many outstanding advantages, such as wide linear ranges, low detection limits, excellent sensitivity, selectivity and stability confirmed that the PBL-II/CPE has promising analytical performance. Meanwhile, the electrode was successfully used for the determination of PC and HQ in local tap water sample and the results are satisfactory.