Caesium ion-selective electrode based on 15-crown-5-phospho-tungstic acid precipitates

A caesium ion-selective PVC membrane electrode based on 15-crown-5-phosphotungstic acid (PW) precipitates as the neutral carrier was prepared. The electrode gave a linear response with a Nernstian slope of 60 mv decade-1 within the concentration range 10-1 to 10-4 M CsNO3. The selectivity and response time of the electrode were investigated and it was found that the electrode exhibited good selectivity for caesium in comparison with alkali, alkaline earth and some transition metal ions. The effects of pH, addition of ethanol and anions present in the test solutions were also studied. (author)