Amperometric determination of hydrogen peroxide on surface of a novel PbPCNF-modified carbon-ceramic electrode in acidic medium

This work describes the electrochemical behavior of lead pentacyanonitrosylferrate (PbPCNF) film immobilized on the surface of carbon-ceramic electrode (CCE) and its electrocatalytic activity toward the reduction of hydrogen peroxide in acidic medium. The electrode was prepared by electroless derivatization of Pb-doped carbon-ceramic electrode surface to the redox active PbPCNF solid film, in the presence of sodium pentacyanonitrosylferrate, Na2[Fe(CN)5NO], (PCNF). The morphology and the composition of the PbPCNF-modified CCE were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and Fourier transform infrared (FTIR) techniques. Various experimental parameters influencing the electrochemical behavior of the modified electrode were optimized by varying the supporting electrolyte, potential scan rates and solution pH. The modified electrode showed an excellent electrocatalytic behavior toward the reduction of hydrogen peroxide in 0.5 M KNO3 at pH 4. The sensor exhibited a good linear response for H2O2 concentration over the range 0.5–58.75 μM with a detection limit of 0.4 μM (S/N = 3). The interferences of dopamine (DA), uric acid (UA), and ascorbic acid (AA) were negligible in the determination of H2O2. The proposed sensor showed good stability, reproducibility and outstanding for long-term use.