Renewable New Copper Complex Bulk‐Modified Carbon Paste Electrode: Preparation,Electrochemistry, and Electrocatalysis

A conductive carbon paste electrode (CPE) comprised of a new copper‐complex of Cu₂(Dpq)₂(Ac)₂(H₂O)₂](ClO₄)₂?H₂O (Dpq=dipyrido3,2‐d : 2′,3′‐f]quinoxaline, Ac=acetate) and carbon powder, was fabricated by the direct mixing method. The electrochemical behavior and electrocatalysis of the new copper‐complex modified CPE (Cu‐CPE) have been studied in detail. Cyclic voltammograms showed that the Cu‐CPE had a favorable electrochemical response of a reversible redox couple of Cu(II)/Cu(I). The Cu‐CPE showed good electrocatalytic activity toward the reduction of the bromate, nitrite and hydrogen peroxide. The electrocatalytic reduction peak current of KBrO₃, KNO₂ and H₂O₂ showed a linear dependent on their concentrations. All of the results revealed that the Cu‐CPE had a good reproducibility, remarkable long term stability and especially good surface renewability by simple mechanical polishing in the event of surface fouling, which is important for practical application.