Construction of Cu2+-selective electrode and thermodynamic study of the ternary aqueous mixed electrolyte system (CuCl2, KCl, H2O) using nanocomposite-based potentiometric sensor

Document Type : Reasearch Paper


1 Department of Chemistry, Faculty of Science, Islamic Azad University, Qeshm, Iran.

2 Department of Chemistry, Faculty of Science, Islamic Azad University, Rasht, Iran.



A nanocomposite membrane Cu2+ ion-selective electrode has been constructed using a new compound ethyl 1,2,3,4-tetrahydro-4-(4-methoxyphenyl)-6-methyl-2-oxopyrimidine-5-carboxylat (ETMOC) as a neutral ionophore. The electrode works properly. It responds to Cu2+ ion with a sensitivity of 29.5 ± 0.2 mV/decade over the range 1.0 × 10−9 to 5.0 × 10−1M at pH 3.0-8.0. The limit of detection was 4.5 × 10−10 M. It has a response time of < 6s and can be used for at least 3 months without any divergence in potentials. The proposed electrode shows fairly good discrimination of Cu2+ ion from several cations. Then, electrolyte solution system, CuCl2, KCl, H2O in the concentration range from dilute to near saturate from the thermodynamic viewpoint was investigated. The thermodynamic investigations were performed based on Pitzer ion-interaction model by processing experimental data of potentiometric. The thermodynamic investigations were successfully performed by the evaluation of potentiometric experimental data.