Determination of hydrazine by polyNi(II) complex modified electrodes with a wide linear calibration range

• Published in: Electrochimica acta 2011-06, Vol.56 (16), p.5766-5770
• Main Authors: Azad, Uday Pratap, Ganesan, Vellaichamy
• Format: Article
• Language: English
• Subjects: Applied sciences; Calibration; Chemically modified electrodes; Chemistry; Diffusion; Diffusion barriers; Drinking water and swimming-pool water. Desalination; Electrocatalysis; Electrochemistry; Electrodes; Electrodes: preparations and properties; Electropolymerization; Exact sciences and technology; General and physical chemistry; Glassy carbon; Hydrazine oxidation; Hydrazines; Nafion; Other electrodes; Oxidation; Pollution; Reaction kinetics; Water treatment and pollution
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2011.04.051

► [NiII(teta)]2+ modified electrodes used for electrocatalytic oxidation of hydrazine. ► Nafion and polymeric [NiII(teta)]2+ films create barrier for hydrazine diffusion. ► Wide linear calibration ranges are obtained for the determination of hydrazine. Polymeric [Ni II(teta)] 2+ (poly(Ni); teta = C-meso-(5,5,7,12,12,14-hexamethyl-1,4,8,11-tetra-azacyclotetradecane)) modified glassy carbon and Nafion (Nf)-coated glassy carbon electrodes (GC/poly(Ni) and GC/Nf/poly(Ni), respectively) were used for the efficient electrocatalytic oxidation of hydrazine (HZ) in 0.1 M NaOH. The catalytic currents were proportional to the concentration of HZ with a wide linear calibration range (LCR). GC/poly(Ni) had a LCR from 1.0 μM to 10.0 mM, whereas that of GC/Nf/poly(Ni) ranged from 1.0 μM to 100.0 mM. The latter is the widest LCR reported to date. The presence of the Nf film (i.e., in GC/Nf/poly(Ni)) not only increased the stability of the poly(Ni) film but also widened the LCR. The electrocatalytic oxidation of HZ obeyed first-order kinetics with respect to HZ concentration. The kinetic parameters were investigated by cyclic voltammetry and chronoamperometry.