A nano-structured Ni(II)–chelidamic acid modified gold nanoparticle self-assembled electrode for electrocatalytic oxidation and determination of methanol

A nano-structured Ni(II)–chelidamic acid (2,6-dicarboxy-4-hydroxypyridine) film was electrodeposited on a gold nanoparticle–cysteine–gold electrode. The morphology of Ni(II)–chelidamic acid gold nanoparticle self‐assembled electrode was investigated by scanning electron microscopy (SEM). Electrocatalytic oxidation of methanol on the surface of modified electrode was studied by cyclic voltammetry and chronoamperometry methods. The hydrodynamic amperometry at a rotating modified electrode at constant potential versus reference electrode was used for detection of methanol. Under optimized conditions the calibration plots are linear in the concentration range 0–50 mM with a detection limit of 15 μM. The formed matrix in our work possessed a 3D porous network structure with a large effective surface area, high catalytic activity and behaved like microelectrode ensembles. The modified electrode indicated reproducible behavior and a high level stability during the experiments, making it particularly suitable for analytical purposes. - Highlights: ► The Au electrode modified with thin Ni(II)/CHE-AuNP film shows stable and reproducible behavior. ► Long stability and excellent electrochemical reversibility were observed. ► This modified electrode shows excellent catalytic activity for methanol oxidation. ► Combination of unique properties of AuNP and Ni(II)/CHE resulted in improvement of current responses.