Structure and properties of a nanocomposite formed by vanadium pentoxide containing poly(N-propane sulfonic acid aniline)

Synthesis and characterization of new nanocomposites of vanadium pentoxide (V2O5) and a sulfonated, alkylated polyaniline derivative (poly(N-propane s ulfonic acid aniline), PSPAN) are described. These nanocomposites were char acterized using infrared spectroscopy, Xray diffraction (XRD), X-ray absorp tion, and some electrochemical methods, including chronopotentiometry (i.e. charge-discharge curves), cyclic voltammetry, impedance, and electrochemic al quartz crystal microbalance (EQCM). Results indicate the presence of the organic material between the layers of the inorganic matrix, where some su lfonic groups of the polymeric chain interact with the vanadium atom. EQCM experiments have shown that anions have a negligible participation in the c harge compensation process during the oxide/polymer-reduction reactions in the nanocomposite. This phenomenon was attributed to the presence of the ne gatively charge sulfonic group. Results point to the possibility of using t his polymeric material as cathode in secondary lithium batteries, because m ainly Li+ would be involved in the charge compensation process, thus not le ading to changes in the electrolyte composition. The cyclability of the nan ocomposite is higher that the vanadium pentoxide due to the fact that there is not an important swelling process. (C) 2001 Elsevier Science B.V. All r ights reserved.