Nile Blue-hexacyanoferrate carbon paste modified electrode as an amperometric sensor for determination of hydrazine

Abstract

The main problem associated with metal hexacyanoferrates (MHCFs) is their instability at high pH values. We synthesized a new Prussian Blue analogue, Nile-Blue hexacyanoferrate (NBHCF), that remains stable in 0.2 M KOH. A carbon paste (CPE) chemically modified electrode (ME) containing NBHCF was prepared as a stable electrochemical sensor for measuring hydrazine. A detailed characterization of the electrochemical and electrocatalytic behavior of NBHCF was performed using cyclic voltammetric, chronoamperometric, differential pulse voltammetric (DPV) and hydrodynamic amperometric methods. The NBHCF-modified electrode produced reproducible redox peaks and resulted in a linear increase in the oxidation signal of hydrazine with increasing concentration of hydrazine in the range of 0.1-6.0 mM (in hydrodynamic amperometry method (HDA)). The electrode detection limit was 40 μM and possessed a surface coverage of Γ = 2.0 × 10-8 mol cm-2. © TÜBİTAK.