We prepared a novel nickel (II) hydroxide-modified carbon paste electrode (Ni(OH)2-X/CPE) for the electrocatalytic oxidation of formaldehyde. The electrode was prepared by a simple method without the use of linking chemicals. The prepared Ni(OH)2-X/CPE material was characterized by scanning electron microscopy and energy dispersive X-ray spectrometry. The electrochemical performance of the proposed electrode was investigated using cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry. The results indicate that Ni(OH)2-X/CPE exhibits good electrocatalytic activity with regards to formaldehyde oxidation owing to its nanoporous structure and the large surface area of zeolite X. The values of the electron transfer coefficient and the catalytic rate constant were 0.7 and 6.1 × 104 cm3/(mol·s), respectively. Therefore, the proposed electrode, which showed remarkable electroactivity with regards to formaldehyde oxidation with long-term stability and good reproducibility, could be useful in fuel cells.
