Potentiometric Flow Injection Detection of Copper(II) with a Graphite Carbon Electrode

Abstract

A graphite carbon electrode has been evaluated in a potentiometric flow injection system for the detection of Cu²⁺. The electrode response characteristics were investigated by both cyclic voltammetry and potentiometry, and it is suggested that the electrode potential change results in the adsorption of Cu²⁺ at the electrode surface. The carbon electrode was used for the flow injection potentiometric detection of Cu²⁺ in 0.05 mol/L NaAc-0.2 mol/L NaCl at pH of 6.0 carrier solution. A linear response in concentration range of 1x10⁻⁵-1x10⁻² mol/L was obtained with a detection limit of 5x10⁻⁵ mol/L. The electrode described in this paper is simple and low cost.

Key Words:

• Graphite carbon electrode
• Cu²⁺ ion
• Potentiometric detection
• Flow injection analysis