Evaluation of sodium dodecyl sulfate effects; the response of modified carbon paste electrode with nickel oxide nanoparticles in the presence of methanol

Synthesis of nickel oxide nanoparticles (NiO NPs) was carried out by Marrubium astranicum leaf extract. The average of particle sizes for NiO NPs was 40 nm. NiO NPs modified carbon paste electrodes in the absence (CPE/NiO NPs) and the presence of sodium dodecyl sulfate (CPE/NiO NPs/SDS) were examined for the electrocatalytic oxidation of methanol in alkaline solutions. The cyclic voltammograms of modified electrodes showed the redox behavior of Ni(III)/Ni(II) couple. However, the presence of SDS at the surface of the electrode increased the efficiency of the catalyst. The values of charge transfer coefficients (α) for the CPE/NiO NPs and CPE/NiO NPs/SDS in the presence of methanol were estimated at about 0.63 and 0.84. Finally, the electrocatalytic oxidation of methanol at the surface of the CPE/NiO NPs/SDS was studied in the optimum conditions (30 min for immersion time in SDS solution, 0.01 M for SDS concentration and 0.4 M for methanol concentration).