Electrocatalytic Oxidation of Hydrogen Peroxide Using Iodide as Mediator; Application for its Simple and Selective Determination

Abstract

The electrocatalytic oxidation of hydrogen peroxide has been studied by iodide at the surface of carbon paste electrode. Cyclic voltammetry and chronoamperometry techniques were used to investigate the suitability of iodide as a mediator for the electrocatalytic oxidation of hydrogen peroxide in aqueous solution with various pH. Results showed that pH 8.00 is the most suitable for this purpose. The kinetic process of the catalytic reaction can be explained using cyclic voltammetry and chronoamperometry. The calculated mean value of catalytic rate constant (kh) is determined to be 6.46 × 102 M−1s−1 using chronoamperometry data. In order to obtain the diffusion coefficient of iodide, chronoamperometry method has been used, that the value of D has been calculated 7.16 × 10−1 cm2 s−1. The catalytic oxidation peak current was linearly dependent on the hydrogen peroxide concentration and the linearity range obtained was 1.00 × 10−5 to 1.00 × 10−3 M. Detection limit has been found to be 5.61 × 10−6 M (3σ;). This method can provide a simple and low cost electrochemical sensor for catalytic oxidation detection of hydrogen peroxide in real sample.

A New Redox Mediator (Cupric‐Neocuproine Complex)‐ Modified Pencil Graphite Electrode for the Electrocatalytic Oxidation of H2O2: A Flow Injection Amperometric Sensor

“…For example, pencil leads used as electrode material are much cheaper than other carbon based electrodes, added to the facts that PGE has functions of disposability, commercial availability and ease of modification. Moreover, the amperometric response of H 2 O 2 was measured at a significantly more negative potential value at [Cu(Nc) 2 ] 2+ /Nf/PGE (+350 mV) compared to that of 4‐amino‐TEMPO‐ERGO/GCE (+750 mV) and GCE/f‐MWCNT@ Mn(bpy) 2 (H 2 O) 2 /Nf (+650 mV), owing to the ease of oxidation of H 2 O 2 with bis(neocuproine)copper(II) chelate complex which could not be observed for other redox mediators used for electrode modification …”

“…Another example was the use of MWCNT‐modified basal plane pyrolytic graphite electrode, though claimed to improve the redox currents and at the same time to decrease the overvoltage for hydrogen peroxide reduction and oxidation, could only start oxidation currents at potentials more positive than 0.8 V . The comparison of the efficiency of some redox mediators used in electrocatalysis of H 2 O 2 oxidation revealed that either Pt electrode with Pt/Ag‐nanoparticles as mediator or carbon paste electrode with manganese oxide mediator at neutral pH could only provide an electrocatalytic effect less than 0.2 V for overcoming the oxidation overpotential of H 2 O 2 . Likewise, in the electrocatalytic oxidation of hydrogen peroxide on the surface of nano‐zeolite modified carbon paste electrode (in which Ni(II) ions were doped into the zeolite matrix), no significant attenuation shift in the overpotential could be seen for H 2 O 2 oxidation, because the peak belonging to redox mediating Ni(II)‐Ni(III) oxidation (in alkaline medium) emerged at about 0.6 V .…”

Electrocatalytic Sensor for Hydrogen Peroxide Based on Immobilized Benzoquinone

“…Notably, BQ belongs to these few materials. Such redox mediators as nitroxides (TEMPO) [40,41] or iodide [42,43] require a higher potential. The catalysts based on inorganic oxides [44][45][46] provide oxidation of hydrogen peroxide at some lower potential but the selectivity was not reported in that works while a catalytic activity of inorganic materials is usually poor selective [47].…”

The quantitative determination of hydrogen peroxide by voltammetry on the carbositall electrode

“…The pharmacopoeian method for determining H 2 O 2 is the method of permanganometric titration [2]. The extensive literature survey reveals that the most common method of the H 2 O 2 analysis is spectrophotometry [20,26,32], fluorimetry [16], luminescence [30,34], various types of chromatography [9,29,31,33], electrochemical [6,7,12,15,27] and other methods of analysis [10,11,32].…”