Novel Triiodide PVC-Based Membrane Sensor Based on a Charge Transfer Complex of Iodine and Bis(2-hydroxyacetophenone)butane-2,3-dihydrazone

Abstract

In this study a novel triiodide ion-selective electrode based on a charge transfer complex of iodine and Bis(2-hydroxyacetophenone)butane-2,3-dihydrazone (ICT), as a membrane carrier was prepared. The electrode has a linear dynamic range between 1.0 <TEX>${\times}$</TEX> <TEX>$10^{-2}$</TEX> and 5.0 <TEX>${\times}$</TEX> <TEX>$10^{-7}$</TEX> M, with a Nernstian slope of 58. 99 <TEX>${\pm}$</TEX> 0.3 mV <TEX>$decade^{-1}$</TEX> and detection limit of 3.0 <TEX>${\times}$</TEX> <TEX>$10 ^{-7}$</TEX> M. The potentiometric response of the proposed sensor is independent of the pH of the solution in the pH range of 3.0-10.0. The electrode possesses the advantages of short conditioning time, fast response time, and especially, very good selectivity over a large number of common organic and inorganic anions. The electrode can be used for at least 6 months without any considerable divergences in the potentials. It was used as an indicator electrode in potentiometric titration of triiodide ion with thiosulfate.