Why is Gold such a Good Catalyst for Oxygen Reduction in Alkaline Media?

P. QUAINO; N.B. LUQUE; R. NAZMUTDINOV; E. SANTOS; W. SCHMICKLER

Angewandte Chemie - International Edition

Wiley-VCH Verlag GmbH& Co. KGaA

Lugar: Weinheim; Año: 2012 vol. 51 p. 12997 - 13000

1521-3773

The two faces of gold: The reduction of oxygen on gold electrodes in alkaline solutions has been investigated theoretically. The most favorable reaction leads directly to adsorbed O2- , but the activation energy for a two-step pathway, in which the first step is an outersphere electron transfer to give solvated O2-, is only slightly higher. d-band catalysis, which dominates oxygen reduction in acid media, plays no role. The reason why the reaction is slow in acid media is also explained.