Catalytic electroxidation pathway for the polymerization of polypyrrole in the presence of ultrafine silver nanoparticles

In this work, we report the first electrochemical polymerization of polypyrrole (PPy) on Au substrates in aqueous solutions containing additives of prepared Ag nanoparticles with a diameter less than 2 nm. Due to the effect of Ag nanoparticles, which can provide a catalytic electroxidation pathway for the polymerization of PPy, the synthesized PPy film demonstrates some novel characteristics. It shows a finer and granular raspberry morphology with nano-scaled particles, and a rougher surface. The conductivity of PPy is significantly increased (∼8 times), which also reflects on the extremely high oxidation level of 0.35 revealed from the analysis of X-ray photoelectron spectroscopy (XPS). The mechanism of the nucleation and growth was investigated to explain the specific characteristics of PPy films.