Preparation, Electrochemical Property and Application in Bulk-modified Electrode of Dawson-type Phosphomolybdate-doped Polypyrrole Composite Nanoparticles1

A kind of inorganic-organic hybrid semiconductor composite nanoparticles: Dawson-type phosphomolybdate-doped polypyrrole (P2Mo18-PPy) was designed and prepared using microemulsion oxidation-polymerization at room temperature and characterized by TEM and IR. The P2Mo18-PPy was used as a bulk-modifier to fabricate a chemically modified carbon paste electrode(CPE) by direct mixing, which represents the example of polyoxometalates(POMs)-doped semiconductor polymer nanoparticles modified electrode. Both the advantage of POMs-doped polymer and the surface-renewal property of the CPE were fully utilized. The electrochemical behavior of the P2Mo18-PPy bulk-modified CPE (P2Mo18-PPy-CPE) was investigated with cyclic voltammetry. Three couples of reversible redox peaks were observed in the range from + 800 to 0 mV, which corresponded to the reduction and oxidation through two-, four- and six-electron processes, respectively. The P2Mo18-PPy-CPE showed a high electrocatalytic activity for the reduction of nitrite, which expanded the application of POMs-doped semiconductor polymer nanoparticles.