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This work addresses the electrocatalytic activity of a new catalyst composed of nickel and manganese binary oxides, prepared by electrodeposition, toward glucose electro-oxidation in alkaline medium. Cyclic voltammetry, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to characterize those electrocatalysts. It has been found that the electrocatalytic activity critically depends on the loading level and the order of deposition of the two oxides; the NiOx/MnOx/GC electrode (MnOx deposited first) showed an excellent electrocatalytic activity and stability toward glucose oxidation compared to NiOx/GC, MnOx/GC or MnOx/NiOx/GC electrodes (NiOx deposited first). At the present work conditions, it has found that, the optimum loading level is 60 cycles of MnOx followed by 10 min deposition of nickel. At this loading level, it has been found that, the relation between Ip/v1/2 function and scan rate gives the characteristic feature of a catalytic process.

A novel binary electrocatalyst fabricated from manganese and nickel oxides nanoparticles (MnOx and NiOx), prepared by electrodeposition, is proposed as an anode for an amplified electrochemical oxidation of glucose in NaOH solutions. Cyclic voltammetry and scanning electron microscopy images were used to characterize these electrocatalysts. It has been found that the electrocatalytic activity critically depends on the order of the deposition of the two oxides. The NiOx/MnOx/GC electrode (MnOx deposited first) showed a superior electrocatalytic activity towards glucose oxidation compared to NiOx/GC, MnOx/GC or MnOx/NiOx/GC electrodes (NiOx deposited first). The extraordinary activity obtained at the NiOx/MnOx/GC electrode is attributed to the compilation of the better adsorption of glucose molecules on the MnOx sites and the increase of conductivity of the NiOx due to the increase of Ni3+ content. The results lead us to conclude that there is a synergism between the two oxides towards the electrooxidation of glucose.