Electrocatalytic Oxidation of Formaldehyde on Novel Composite of Nickel/triton-x100/poly(o-aminophenol-coaniline)

Oxidation of formaldehyde (HCHO) is very important, due to its use in fuel cells. Modification of electrodes surfaces is an excellent way to decrease the over potentials while to increase the current density of the voltammetric response.pt as most efficient metal catalyst can easily be poisoned by product of oxidation at a high cost. In this work, an efficient and low cost electrocatalytic system for electrochemical oxidation of formaldehyde in alkaline solution is introduced. For preparation of this modified electrode, copolymeric film on the surface of carbon paste electrodewas formed by successive potential cycling in solution containing o-aminophenol and aniline as monomer and Triton X-100 as a surfactant. Ni(II) ions were incorporated into the electrode surface by immersion of the copolymeric modified electrode in 0.1 M Ni(II) ion solution. The influences of different parameters such as mol ratio of monomers in copolymer formation and the number of potential cycling for copolymer formation on electrocatalytic ability of the modified electrode for formaldehyde oxidation have been investigated and optimized. Results show that modified electrode with copolymeric films, had a higher catalytic effect for formaldehyde oxidation with respect to pure homopolymers (polyaniline or poly(o-aminophenol)). Also addition of Triton -X100 in electropolymerization step, considerably increased catalytic ability of the modified electrode for formaldehyde oxidation. This modified electrode displays a highly efficient electrocatalytic activity toward oxidation of formaldehyde. The current density of 11 mA cm-2 is greater than most of the previously reported electrodes.