Potentiometric Membrane Electrode for Cr(III) Ion Based on a New Aryl Amide Bifunctional Bridging Ligand as a Neutral Carrier

作者：Ma Yu Hua; Yuan Ruo; Chai Ya Qin; Liu Xin Lu

来源：Journal of the Chinese Chemical Society, 2009, 56(4): 676-682.

DOI：10.1002/jccs.200900101

• PVC membrane
• Cr(III) ion-selective electrode
• Aryl amide bifunctional bridging ligand
• Potentiometric response characteristic

A novel Cr(III) ion-selective electrode is constructed by incorporating a new aryl amide bifunctional bridging ligand, 2,2'-bis {[(2 ''-benzylaminoformyl)phenxoyl]methyl}-diethylether (BBPMD) as a neutral carrier into the PVC matrix. The proposed electrode, with optimum membrane composition, exhibits an excellent near-Nernstian response for Cr(3 ) ion ranging from 2.8 x 10(-6) to 1.0 x 10(-1) mol/L with a detection limit of 8.6 x 10(-7) mol/L and a slope of 19.5 /- 0.2 mV/dec in pH 3.0 nitrate buffer solution at 25 degrees C. It has an appropriate response time, suitable reproducibility, and good selectivity towards Cr(3 ) ion. The operational pH range of the proposed electrode is 2.5-6.5. The response mechanism was discussed in view of UV-vis spectroscopy and the A.C. impedance technique. The excellent analytical features of the proposed electrode could lead to its successful application as an indicator electrode in potentiometric titration of Cr(3 ) ion and in the direct determination of Cr(3 ) ion in tea leaves and coffee samples.

• 出版日期2009-8
• 单位西南大学