An Efficient Amperometric Sensor for Hydrogen Peroxide by Using a Carbon Paste Electrode Modified with Cobalt Impregnated Zeolite

Abstract

Cobalt impregnated zeolite-modified electrode was prepared by mixing cobalt-zeolite (Co-Z) and graphite powder with different percentages. Using the cyclic voltammetric technique, the electrochemical oxidation of hydrogen peroxide at such electrodes was investigated. Experiments on zeolite show that it is not electrochemically active towards hydrogen peroxide oxidation in NaOH solution. The presence of cobalt ions in the zeolite matrix, by soaking the electrode in an aqueous Co(NO 3 ) 2 solution, markedly enhances the electrocatalytic activity which was found to depend on the cobalt content. On the other hand, the presence of zeolite and/or Co metals in the catalyst is essential; however, the electro-catalytic activity depends on different percentages of Co-Z. Under the selected conditions, the anodic peak current was linearly dependent on the concentration of the hydrogen peroxide in the range 0.03-9 and 0.006-0.1 mM with CV and amperometric methods, respectively. The detection limits (S/N=3) were also estimated to be 17 and 2.5 µM.

Hydrothermally driven three-dimensional evolution of mesoporous hierarchical europium oxide hydrangea microspheres for non-enzymatic sensors of hydrogen peroxide detection

“…5D, this non-enzymatic sensor can allow H 2 O 2 detection with a wide linear range from 0.5 to 500 μM with a linear correlation coefficient of R = 0.9995 and a high sensitivity of 15.4 μA mM −1 . The low detection limits achieved in this study are comparatively lower than the detection limits of the poly(p-aminobenzene sulfonic acid)-modified glassy carbon electrodes, 23 nanocomposite carbon-maghemite nanoparticle electrode, 24 ferric oxide nanoparticle-modified carbon electrodes, 25 cobalt-impregnated zeolite-modified carbon paste electrode, 26 silver particles patterned on single-walled carbon nanotubes, 27 silver nanoparticles supported on reduced graphene oxide, 28 roughened macroporous gold/platinum nanoparticle electrode, 29 sodium alginate and horseradish peroxidase co-deposition electrode, 30 Environmental Science: Nano Communication dendritic silver nanostructure electrode, 31 immobilized hemoglobin (Hb) on DNA/poly-2,6-pyridinediamine (PPD)-modified Au electrode, 32 and gold nanoparticles supported on polyoxometalatefunctionalized graphene tri-component nanohybrids. 33 Such excellent performance is accredited to the high exposure of electrocatalytically active sites on the nanosheets of the Eu 2 O 3 mesoporous hydrangea microspheres.…”