Fabrication of silver nanoparticles–polypyrrole composite modified electrode for electrocatalytic oxidation of hydrazine

An electrochemical sensor was fabricated by electrodeposition of silver nanoparticles on pre-synthesized polypyrrole (PPy) nanofiber, forming a silver nanoparticle/PPy composite matrix on glassy carbon electrode (Ag/PPy/GCE). The electrochemical behavior and electrocatalytic activity of Ag/PPy/GCE were characterized by cyclic voltammetry. As an electrochemical sensor, the Ag/PPy/GCE exhibited strong catalytic activity toward the oxidation of hydrazine. The morphology of electrodes was characterized by scanning electron microscopy (SEM). The kinetic parameters such as the electron transfer coefficient (α) and the catalytic rate constant (kcat) for the oxidation of hydrazine were determined. The diffusion coefficient (D) of hydrazine in solution was also calculated by chronoamperometry. The detection limit of hydrazine was found to be 0.2 μM. Moreover, the sensor showed excellent sensitivity, selectivity, and stability.