Facile synthesis of polypyrrole-zirconium(IV) oxide-ethanolamine anion exchange nanocomposite and its utilization in membrane electrode development for sensing and quantitative detection of As(III) in water

A new electrically conductive polypyrrole-zirconium oxide-ethanolamine (PPy-ZrO-EA) anion exchange nanocomposite was synthesized by polymerizing pyrrole in presence of zirconium oxideethanolamine (ZrO-EA) via a facile oxidative chemical polymerization approach. Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis (TGA) and derivative thermogravimetric analysis (DTG) data revealed the formation and structure of PPy-ZrO-EA. Strong interactions between PPy and ZrO-EA particles was observed. A better thermal stability was exhibited by the nanocomposite as compared to PPy. The material was highly efficient for electroanalytical applications as ionic sensor. It was developed into a membrane electrode for detecting As(III) in aqueous solutions. The best results were obtained for the membrane electrode with linear potential response in 10×10^-1-10×10^-8 M As(III) concentration range with 29.71 mV/decade (R2 = 0.9999) slope. The electrode's useful pH was found in 5.0-10.0 range. The values of selectivity coefficients indicated significant selectivity for As(III) ions with respect to interfering anions. Drinking water samples added with As(III) salts of known concentrations were used to determine the accuracy of membrane electrode. The results obtained were equivalent to those achieved with a standard portable coulometric arsenic analyzer.