IFEG   20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Electrocatalysis at nanostructured electrodes: a unified model
Autor/es:
KAY PÖTTING, WOLFGANG SCHMICKLER AND ELIZABETH SANTOS
Lugar:
Sevilla, Espana
Reunión:
Congreso; The 59th Annual Meeting of the International Society of Electrochemistry; 2008
Resumen:
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Recently, we have proposed a unified model for
electrochemical electron transfer reactions on metals, which explicitly
accounts for the electronic structure of the electrode. Our approach applies
the SKS-Hamiltonian [1] for concerted bond breaking and electron-transfer
reactions at metal electrodes; it contains the contributions of the molecule,
the metal which acts as a catalyst, the solvent and the corresponding interactions
between these subsystems. First calculations had been performed within the
wideband approximation for the electronic structure of the metal and the
extended Hückel approximation for the molecule [1,2]. Later, we have introduced idealized band
shapes [3,4]. Finally, we have performed calculations for a real system, namely
the hydrogen oxidation reaction, including explicitly the band structure of
different metals obtained from the Density
Functional Theory (DFT) [5,6]. The results showed a good correlation
between the calculated energies of activation and the exchange current
densities the first such correlation based on a theory. Now, we want to
follow up and we have abandoned the tight-binding approximation, by which we
have previously described the hydrogen molecule and included results from DFT also for the reactant.