Effects of FeCl_3/APS composite oxidant on electrochemical properties and structure of polyaniline prepared by emulsion polymerization

Polyaniline(PANI) doped with dodecylbenzenesulfonic acid was prepared by emulsion polymerization using ferric chloride(FeCl3) and ammonium persulfate(APS) as composite oxidant for the first time.The effects of FeCl3 and APS molar ratio(n(FeCl3)/n(APS)) and the molar ratio of composite oxidant and An(n(composite oxidant(cod))/n(An)) on the electrochemical properties of PANI were discussed by cyclic voltammogram(CV) and Tafel curve using the carbon paper loaded PANI as working electrode.The characterization results of the electrochemical properties of PANI were proved by contrast analysis of the thermal stability of conductivity,X-ray diffraction(XRD) and thermogravimetric analysis(TGA) of PANI.The experimental results showed that compared with PANI prepared by APS,PANI prepared by composite oxidant there were larger redox current,higher corrosion potential and better thermal stability of conductivity when n(FeCl3)/n(APS) is 3.5∶1 and n(cod)/n(An) is 3∶1.The results of XRD and TGA indicated that PANI prepared by composite oxidant had better crystallinity and thermal stability.