AgNP-“Zeolite A”/NG as a Novel Nanocatalyst for Methanol Electro-Oxidation in Alkaline Setting

Abstract

In this research, the glassy carbon electrode was modified by silver nanoparticles zeolite type A composite, hybridized with the nitrogen-doped graphene (AgNP-“zeolite A”/NG). The electrocatalytic oxidation of methanol was investigated at the surface of the modified electrode in alkaline solution using cyclic voltammetry, chronoamperometry and linear sweep voltammetry methods, and followingly, excellent electrocatalytic activity was observed. The structure and morphology of the resulting AgNP-“zeolite A”/NG were characterized by scanning electron microscopy, dynamic light scattering, X-ray diffraction, Fourier transform infrared spectroscopy and Raman spectroscopy techniques. This electrode was found as a good candidate for application in the anode pole of the direct methanol fuel cell. Silver incorporated in this modified electrode played a key role for oxidation of methanol. The results confirmed the adsorption-controlled reaction at the surface of the modified electrode. Also, the effect of some parameters such as pH, scan rate of potential and the concentration of methanol were explored. Moreover, the kinetic parameters such as transfer coefficient (ko) and exchange current (io) were obtained 1.199 × 10−7 and 2.18 × 10−4 A, respectively, for methanol electro-oxidation process by the AgNP-“zeolite A”/NG. The relative standard deviation of ten replicate measurements, performed on a single electrode in 1.5 × 10−4 M of methanol in alkaline setting, was calculated 2.1% too.