Preparation of hybrid cobalt–iron hexacyanoferrate nanoparticles modified multi-walled carbon nanotubes composite electrode and its application

• Hybrid Co-FeHCF nanoparticles are electrodeposited using MWCNT as template.
• Electrochemical behavior of cobalt–iron MHCF is different with CoHCF and PB.
• Co-FeHCF has high electrocatalytic activity to the oxidation of isoniazid.

The hybrid cobalt–iron hexacyanoferrate nanoparticles modified electrode has been fabricated by electrochemical methods using MWCNT as a template. The electrochemical properties as well as the kinetic parameters such as the electron transfer coefficient α, rate constant ks of the electrode reaction and the catalytic rate constant kcat of the catalytic reaction are determined. Isoniazid was chosen as a model compound to elucidate the electrocatalytic activity of the resulting modified electrode. The results showed that this modified electrodes exhibited good stability and high electrocatalytic activity to the oxidation of isoniazid. Hydrodynamic amperometry was applied for the determination of isoniazid with linear range of 2.0 × 10−7 to 1.0 × 10−4 mol L−1, The detection limit and sensitivity was 8.0 × 10−8 mol L−1 and 114.9 μA mM−1, respectively.