Polyaniline-carbon composite films as supports of Pt and PtRu particles for methanol electrooxidation

Vulcan XC-72 carbon black particles (average size: ca. 50 nm) was incorporated into polyaniline (PANI) matrix by an electrochemical codeposition technique during the electropolymerization process. The doping by carbon particles leads to a higher polymeric degree and a lower defect density in the PANI structure. Furthermore, the incorporation of carbon particles not only increases the electrochemical accessible surface areas (Sa) and electron conductivity of the PANI film, but also decreases charge transfer resistance at PANI/electrolyte interfaces. Therefore, as expected, a fabricated PANI + C composite film with dispersed Pt and PtRu particles exhibited excellent electrocatalytic activity for methanol oxidation due to better Pt dispersion and utilization. The PANI + C composite film is more promising as a support material in electrocatalysis than a PANI film. Meanwhile, a new application for regular carbon black as a doping material into conducting polymer for electrocatalysis was thus demonstrated.