Research on Electrochemical Oxidation of Formaldehyde on the Nanoporous Silver Electrode in Alkaline Solution

Nanoporous silver was fabricated by dealloying Ag 25 Zn 75 , then characterized by field emission scanning electron microscopy and cyclic voltammetry. The surface area of nanoporous silver was 62 times larger than that of dense silver according to the enhancement of the charge associated with the reduction of adsorbed oxygen. In 0.9 M KOH solution with 0.3 M formaldehyde, there exists oxidation of formaldehyde on the nanoporous silver electrode, showing the electrochemical catalytic activity toward formaldehyde. And the process is confirmed to be controlled by the diffusion. With increasing scanning cycles, coarsened and accumulated ligaments appeared, and the oxidation current density decreased simultaneously.