Electroanalysis of copper as a heavy metal pollutant in water using cobalt oxide modified exfoliated graphite electrode

► We fabricated EG electrodes and used it as an electrochemical sensor for Cu2+ ions. ► Using CoO modified EG electrode, a low detection limit of 94 μg L−1 was achieved. ► Good reproducibility was observed on the modified electrode. ► Electroanalysis of real water sample was carried out with good % recovery.