Chemical syntheses of the conducting material formed by heteropolyacids and polyaniline

Here we report a hybrid organic-inorganic conducting material formed by van adium-containing silicotungstic/molybdic or phosphotungstic/molybdic acid a nd polyaniline (PAN) with a one-step or a two-step chemical reaction involv ing oxidation of aniline with ammonium persulfate in the presence of vanadi um-containing silicotungstic/ molybdic or phosphotungstic/molybdic acid. Po lymer structure was examined by elemental analysis, IR, XRD, XPS, and therm al stability and conducting behavior was studied. Results showed that the c omposition and structure of main chain with one-step method were similar to that with two-step method. However, some differences in XRD spectra betwee n the polymer with one-step and two-step methods were observed, which may b e due to differences of doping methods. Conductivity of materials with a on e-step method was bigger than that with a two-step method when the percenta ge of doping was determined. When heteropolyacid as doping agent was determ inate, conductivity increased with doping percentage at the beginning and r ate of conductivity was faster in the two-step method than in the one-step method. However conductivity did not increase with doping percentage when t he doping percentage increased to a certain range. The conductivity of the materials descended after the materials were heated. One reason was dedopin g or degradation of the materials.