Nickel(II) Ion-Selective Electrode Based on 2-Methyl-4-(4-methoxy phenyl)-2,6-diphenyl-2H-thiopyran

A new PVC membrane electrode for nickel ion based on a recently synthesized 2-methyl-4-(4-methoxy phenyl)-2,6-diphenyl-2H-thiopyran as membrane carrier was prepared. The sensor exhibits a Nernstian response for Ni2+over a wide concentration range (5×10–2–2×10–5 M) with a limit of detection of 9×10–6 M. The response time of the sensor is ca. 10 s and the membrane can be used for more than 8 weeks without observing any deviation. The proposed membrane sensor shows excellent discriminating ability towards Ni2+ ion in comparison to several alkali, alkaline earth, transition and heavy metal ions. It was used as an indicator electrode in potentiometric titration of Ni ions in both water and 85% acetonitrile solutions.