Electrodeposited AgPd alloy coatings as efficient catalysts for the ethanol oxidation reaction
By Lovi?, J. D.; Elezovi?, N. R.; Jovi?, B. M.; Zabinski, P.; Gaji?-Krstaji?, Lj; Jovi?, V. D.
Published in International Journal of Hydrogen Energy
2018
Abstract
The Pd and three AgPd alloy layers (AgPd1, AgPd2 and AgPd3) were electrodeposited onto Au disc electrodes from the solution containing high concentration of chloride ions (>12 M). All coatings were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), anodic linear sweep voltammetry (ALSV), while their surface composition was investigated by X-ray photoelectron spectroscopy (XPS). The AgPd1 and AgPd2 samples were electrodeposited at different constant current densities (?0.178 mA cm?2 and -0.415 mA cm?2 respectively) to the charge of ?0.2 C cm?2 (thickness ? 0.18 ?m) at a stationary disc electrode, while the sample AgPd3 was electrodeposited to the charge of ?3.0 C cm?2 (thickness ? 2.8 ?m) at a constant current density of ?7.0 mA cm?2 under the conditions of convective diffusion. Samples AgPd1 and AgPd2 had similar morphologies of low roughness, while the morphology of AgPd3 was characterized by large crystals and higher roughness. The most active and the most poisoning tolerant coatings for ethanol oxidation reaction (EOR) are the AgPd3 and AgPd1 alloy samples, containing 72.6 at.% Ag