IFEG 20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
artículos
Título:
A model for the Heyrovsky reaction as the second step in hydrogen evolution
Autor/es:
E. SANTOS; P. HINDELANG; P. QUAINO; W. SCHMICKLER
Revista:
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
Editorial:
ROYAL SOC CHEMISTRY
Referencias:
Año: 2010
ISSN:
1463-9076
Resumen:
On a number of electrodes the second step in hydrogen evolution is the reactionof a proton with an adsorbed hydrogen intermediate to form a molecule,which is also known as the Heyrovsky reaction. We have developed a modelHamiltonian for this reaction, which for concrete applications requires extensivecalculations on the basis of density-functional theory. Explicit resultsare presented for a Ag(111) electrode. The rate-determining step is electrontransfer to the proton that approaches the electrode from the solution. Atthe saddle point for this reaction the adsorbed hydrogen atom has moved alittle away from the surface in order to reduce the repulsion of the productmolecule. Electron transfer to the proton occurs when the distance betweenthe two particles is close to the bond distance of the hydrogen molecule.
