Solid Contact Nitrate Ion-Selective Electrode Based on Ionic Liquid with Stable and Reproducible Potential

A simple, fast and cheap method of preparation of solid contact nitrate ion-selective electrode is proposed. The electrode membrane phase consist of only three components: PVC, plasticizer and ionic liquid (IL).The ionic liquid trihexyltetradecylphosphonium chloride is used in triple function as ionophore, as lipophilic ionic component in order to reduce membrane resistance, and as transducer media in order to stabilize the potential of internal Ag/AgCl electrode. The electrical properties of the membrane were studied by electrochemical impedance spectroscopy and the influence of the interfacial water film was evaluated by potentiometric water layer test.