Electrocatalytic Oxidation and Voltammetric Determination of Hydrazine at Bulk-Modified Carbon Paste Electrode with 1-[-4 (Ferrocenyl Ethynyl Phenyl]-1-Ethanone

The electrochemical behaviour of hydrazine studied at the surface of 1-[4-(ferrocenyl ethynyl) phenyl]-1-ethanone (as an organo-metallic mediator) modified carbon paste electrode in aqueous media using cyclic voltammetry (CV) and double step potential chronoamperometry. It has been found, that under optimum condition (pH 8.00) in cyclic voltammetry, the oxidation of hydrazine is occurred at a potential about 300 mV less positive than that an unmodified carbon paste electrode. The kinetic parameters such as electron transfer coefficient, α and the catalytic reaction rate constant, k/h were also determined using electrochemical approaches. The electrocatalytic oxidation peak current of hydrazine showed a linear dependent on the hydrazine concentration and the linear calibration plots were obtained in the ranges of 7.0×10-5 M - 1.8×10-2 M and 8.0×10-6 M - 1.0×10-3 M of hydrazine concentration with CV and differential pulse voltammetry (DPV) methods, respectively. The detection limits (2σ) were determined as 1.4×10-5 M and 1.2×10-6 M by CV and DPV methods. The RSD% for seven replicates determination of 20.0 and 50 μmol L-1 of hydrazine were 1.8 and 1.6%, respectively. This method was also examined as a selective, simple and precise new method for voltammetric determination of hydrazine in real sample.