Electrocatalytic behaviour and application of manganese porphyrin/gold nanoparticle- surface modified glassy carbon electrodes

• Published in: Applied surface science Vol. 390; pp. 131 - 140
• Main Authors: Sebarchievici, I., Tăranu, B.O., Birdeanu, M., Rus, S.F., Fagadar-Cosma, E.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 30.12.2016
• Subjects: Electrocatalysis; Electrodes; Glassy carbon; Gold; Gold nanoparticles; Hydrogen peroxide; Manganese; Manganese porphyrin; Modified glassy carbon electrode; Nanostructure; Oxidation; Reduction; Voltammetry; nAu; Hydrogen peroxide; Gold nanoparticles; GC_MnP; Modified glassy carbon electrode; k; MnP; n; GC_MnP_nAu; E1/2; α; Electrocatalysis; Manganese porphyrin; ia; ic
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2016.07.158

[Display omitted] •Mn-porphyrin/gold nanoparticle-modified glassy carbon electrodes were obtained.•AFM investigations of thin films display multilayer of triangular type architecture.•Oxidation and reduction processes of H2O2 are diffusion controled.•There is a linear dependence between H2O2 concentration and the currents intensity.•The modified electrodes show better electrochemical detection ability to H2O2. The main purpose of this research was to obtain manganese porphyrin/gold nanoparticle-modified glassy carbon electrodes and to use them for the detection of H2O2. Two sets of modified electrodes were prepared by drop-cast deposition of 5,10,15,20-tetra(4-methyl-phenyl)porphyrinato manganese(III) chloride alone and of the same Mn-porphyrin and gold-colloid solution and comparatively characterized by Raman, UV–vis, ellipsometry, AFM and TEM microscopy, XPS and cyclic voltammetry. XPS spectrum recorded for GC_MnP_nAu modified electrode displayed the characteristic signals of gold nanoparticles. The optical parameters have greater values for GC_MnP_nAu in comparison with GC_MnP, due to increasing charge transfer efficiency. The MnP_nAu film mediates the electron transfer between H2O2 and GC, evidenced by an increase in the current intensity of the anodic peak, and facilitates the electrochemical regeneration of oxidized H2O2 at cathodic potentials. From the cyclic voltammetry experiments a linear relationship between H2O2 concentration vs oxidation and reduction currents was observed. The linear dependence between density of current and the square root of the scan rate indicates that the oxidation and reduction processes of H2O2 are diffusion controlled. The GC_MnP_nAu modified electrode shows great potential as electrochemical sensor for determination of hydrogen peroxide.