Potentiometric flow-injection analysis of alkali and alkaline metals with a tungsten oxide coated nafion film sensor

✍ Scribed by ZuLiang Chen; P. W. Alexander

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 186 KB
• Volume: 9
• Category: Article
• ISSN: 0895-7533
• DOI: 10.1002/(sici)1098-2728(1997)9:4<201::aid-lra6>3.0.co;2-4

✦ Synopsis

Potentiometricflow-injectionanalysisofalkaliand

alkaline metals was possible using a novel type of electrochemical sensor based on tungsten oxide wire coated Nafion electrode. The response characteristics of a tungsten oxide coated Nafion sensor for alkali and alkaline metals were investigated by potentiometric flow-injection measurement. It was found that ion exchange preconcentrated metals by electrostatic interaction and also excluded the anion interference in the presence of Nafion film on the surface of the electrode. This sensor gave a linear response in the range of 4 ‫ן‬ 10 ‫5מ‬ -1 ‫ן‬ 10 ‫2מ‬ M with detection limits of 10 ‫6מ‬ M. The slopes of 39.2 and 44.4 mV/ decade for the K ‫ם‬ and Ca ‫ם2‬ were obtained. Compared to bare electrode, the coated Nafion sensor offered a fast response time (Ͻ10 s), a stable baseline, and no anion interference.