VOLTAMMETRIC BEHAVIOR OF SEVERAL ANIONS IN ACETONITRILE AT PLATINUM-ELECTRODES COATED WITH POLYACRYLAMIDE COUPLED TO COBALT PHTHALOCYANINE

The voltammetric behavior of several anions in acetonitrile (AN) was s tudied at electrodes consisting of polyacrylamide (PAA) coupled to cob alt phthalocyanine (PhCo) and a platinum disk. Well-defined anodic pea ks were obtained by cyclic voltammetry for chloride, bromide, iodide, thiocyanate, and tetraphenylborate ions, while fluoride and cyanide io ns gave broad peaks. The anodic peak current versus concentration plot s were linear for these anions over a concentration range of 1 to abou t 10 mM. Fluoride and cyanide ions were accumulated in the PAA-PhCo me mbrane, and the anodic peak current increased with the standing time t o give well-defined sharp peaks. The anodic peak processes of chloride , bromide and tetraphenylborate ions were diffusion controlled.