Applied Surface Science, 2014, 316, 245-250

Jianqiang Wang^a†, Chao Luo^a†, Genggeng Qi^b, Kai Pan^{a, b}*, Bing Cao^a*

Polyacrylonitrile/polypyrrole (PAN/PPy) core/shell nanofiber mat was prepared through electrospinningfollowed by a simple chemical oxidation method. The polypyrrole-functionalized nanofiber mats showedselective adsorption performance for anions. The interaction between heavy metal anions and polypyrrole(especially the interaction between Cr2O72−and polypyrrole) during the adsorption process was studied.The results showed that the adsorption process included two steps: one was the anion exchange proces**etween the Cl−and Cr(VI), and the other was the redox process for the Cr(VI) ions. The adsorptionamount was related to the protonation time of the PAN/PPy nanofiber mat and increased as protonationtime increased. Meanwhile, the Cr(VI) ions were reduced to Cr(III) through the reaction with aminogroups of polypyrrole (from secondary amines to tertiary amines). PAN/PPy nanofiber mat showed highselectivity for Cr(VI), and the adsorption performance was nearly unaffected by other co-existing anions(Cl−, NO3−, and SO42−) except for PO43−for the pH change.