Fabrication of polypyrrole nanoplates decorated with silver and gold nanoparticles for sensor applications

Abstract

Polypyrrole nanoplates (PPyNPTs) were successfully synthesized via in situ chemical oxidation polymerization of pyrrole molecules. Furthermore, silver and gold nanoparticles (Ag and AuNPs) were assembled onto the as-prepared PPyNPTs by electrostatic interaction to fabricate two nanohybrids of PPyNPT–Ag and PPyNPT–Au, and their structures were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The optimal parameters for creating uniform PPyNPT–Ag and PPyNPT–Au nanohybrids were obtained by controlling the reactive conditions, and the created PPyNPT–Ag and PPyNPT–Au nanohybrids were then immobilized onto glassy carbon electrodes and applied to construct hydrogen peroxide (H₂O₂) and dopamine (DA) sensors. We found that the fabricated sensors with PPyNPT–Ag and PPyNPT–Au nanohybrids are highly specific for sensing H₂O₂ and DA, respectively. The PPyNPT–Ag based H₂O₂ sensor exhibited a fast amperometric response to H₂O₂ with a linear range from 0.01 mM to 3.01 mM and a detection limit of 1.8 μM, and the PPyNPT–Au based DA sensor has a linear detection range from 1 μM to 5.201 mM and a detection limit of 0.36 μM.