Potentiometric Response Properties of Sensor Membranes Based on Cobalt Phthalocyanine Conjugate-Polymer in Nonaqueous Solutions.

Some experiments are carried out in order to clarify the reason why the electrode prepared by coating a platinum disk with a non-plasticized membrane of polyacrylaminde polymer (PAA) coupled to cobalt phthalocyanine (CoPc) shows such a Nernstian response and a special selectivity for fluoride and cyanide ions in acetonitrile (AN). Special interactions between the ions and CoPc are observed spectrophotometrically. A complexing ability of the CoPc with only fluoride and cyanide ions works to respond in a Nernstian way for the ions at the electrode. Since the electrode shows quite poor response to chloride and bromide ions it can be understood that an ion exchange reaction of the ions in the solution at CoPc does not function to the response of the electrode. Furthermore, the PAA matrix of the membrane is found to produce the electrochemical masking effect on chloride and bromide ions. The PAA–CoPc electrode is confirmed as available for use of determining the solubility product constant of sodium fluoride i...