Kinetics of CO2 electroadsorption on electrodispersed platinum electrodes in acid solutions

Abstract

The kinetics of CO, electroadsorption on electrodispersed Pt electrodes have been investigated in different acid electrolytes. The kinetic data obtained at different adsorption potentials, adsorption times and CO, concentrations in solution have been interpreted in terms of two complex reaction mechanisms involving the formation of strongly and weakly bound reduced CO, adsorbates through reactions involving s-H and w-H adatoms, respectively, and carbon dioxide. The reaction mechanism between H adatoms and CO, implies the initial electroadsorption of H atoms, the transport of CO, from the bulk of the solution to the reaction interface, and the formation of the reduced CO, adsorbate. Under certain conditions, particularly when s-H adatoms are involved, the entire reaction approaches mass transport rate control. Conversely, the reaction between w-H adatoms and CO, appears as a rather slow process.

Analysis of Reaction Kinetics for Carbon Monoxide and Carbon Dioxide on Polycrystalline Platinum Relative to Fuel Cell Operation

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Noble metal-free catalysts supported on carbon for CO 2 electrochemical reduction

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