XPS Study of Competing Doping Behavior of Polyaniline

Thestructure and protonation levelof conductive polyaniline (PANI) chemicallysynthesized in different reactive systems have been investigated using X-ray photoelectron spectroscopy (XPS). Polyaniline prepared in hydrochloric acid aqueoussolution easily undergoes deprotonation under prolonging exposure to vacuum at 60℃. When polyaniline was prepared by solution of coexistence of sodium dode-cylbenzene sulfonate (SDBS) and hydrochloric acid, two kinds of counterion (DBS-and Cl-) occurred competing doping behavior. The results reveal that DBS-take part in associating with positively charged polyaniline backbone, and that the N1sand S2pXPS core levelspectraare verysimilar to thatof polyani-line doped by dodecylbenzene sulfonate acid (DBSA) alone.Howerer, SDBS-HCl coexisting system is more favorabale than that of DBSA alone.