Cobalt Ion Selective Electrode Based on ۱۲Crown ۴ and Indigo

A new PVC membrane electrode for Co۲+ ions based on Crown ether ۴ (I) and Indigo dye (II) as an excellentneutral carrier was prepared. The electrode exhibits a Nernstian response for Co۲+ ions over a wide concentrationrange (۱.۰×۱۰−۲ to ۴.۰×۱۰−۷ M) with a slope of ۳۰±۱ mV per decade. The limit of detection is ۱.۰×۱۰−۷ M(۰.۰۰۶ ppm). It has a fast response time of <۵ s and very high lifetime as can be used for at least ۶ monthswithout any divergence in potential. The proposed sensor revealed good selectivities over a wide variety of othercations including alkali, alkaline earth, heavy and transition metals and could be used in the pH range ۵.۰–۸.۰.This electrode was successfully applied for the direct determination of Co۲+ in solution.

کلیدواژه ها:

potentiometery ، PVC membrane ، selective electrode ، Cobalt ، crown ether