Characterization and Electrocatalytic Properties of the Phosphomolybdate-PAMAM Nanocomposite Film

Abstract

The phosphomolybdate-PAMAM nanocomposite film was successfully prepared by using a submonolayer of 3-mercaptopropionic acid (3-MPA) adsorbed on a polycrystalline gold electrode further reacted with poly(amidoamine) (PAMAM) dendrimer (generation 4.0) to obtain a film on which 1:12 phosphomolybdate acid (PMo12) was later coordinated to afford a mixed electrocatalytic layer. On the basis of the electrochemical behaviors, atomic force microscopy (AFM) and X-ray photoelectron spectra (XPS), it is suggested that the PMo12 nanoparticles are located within the dendritic structure of the surface attached PAMAM dendrimers. The protonated environment provided by PAMAM not only promises the higher electroactivity of PMo12 at weak acidic condition, but also improves its stability. It was illustrated experimentally that the hybrid film showed a high electrocatalytic activity for reduction of S2O8 2and H2O2 in the aqueous solution of pH 4.0.