Electrocatalytically active nanocomposite carbon paste electrode modified with SiO2/poly (P-phenylendiamine) core/shell nanoparticles: application toward electro-oxidation of hydrazine

This research highlights fabrication, characterization, and performance of a carbon paste electrode modified by a nanocomposite having poly(P-phenylendiamine) (PpDP) and silica nanoparticles as novel potential electrocatalyst for hydrazine oxidation. The core/shell structure morphology and size of PpDP and its nanocomposite were investigated by scanning electron microscopy and transmission electron microscopy techniques. Catalytic activity and stability of the fabricated carbon paste electrode (CPE) was evaluated using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. The results confirmed that the nanocomposite significantly enhances the catalytic activity of the CPE. The kinetic parameters of the electron transfer coefficient and diffusion coefficient of hydrazine were also determined and compared. It was also evidenced that the core/shell morphology of the nanocomposite improves effective dispersion of silica nanoparticles facilitating the easier access of hydrazine to the catalytic sites.