Fabrication of Solid Contact Ion Selective Electrode for Mercury (II) Using Conductive Polymer Membrane

A solid-contact ion-selective electrode for mercury (II) ions was fabricated to determine Mercury (II) in aqueous environment. A conductive polymer membrane (polypyrrole-PPy) was synthesized electrochemically on paste carbon electrode, which is covered by the ion-selective membrane (ISM) - an important part of a complete solid contact ion selective electrode (SCISE). The electrode showed excellent potentiometric response over a wide concentration range from 10(-9) M to 10(-2) M and detection limit down to 6 x 10(-10) M. A good selectivity towards Hg2+ ions in comparison with other common ions in water has also been observed. The electrode was employed for determination of Hg2+ in ballast water samples with high sensitivity and accuracy.