January 20, 2007
Journal Article

Platinum Monolayer Electrocatalysts for Oxygen Reduction

Abstract

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. We have synthesized a new class of electrocatalysts for the oxygen reduction reaction, consisting of a monolayer of Pt or mixed monolayer of Pt and another late transition metal (Au, Pd, Ir, Ru, Rh, Re or Os) deposited on a Pd(1 1 1) single crystal or on carbon-supported Pd nanoparticles. Several of these electrocatalysts exhibited very high activity, amounting to 20-fold increase in a Pt mass activity, compared with conventional all-Pt electrocatalysts. Their superior activity reflects a low OH coverage on Pt, caused by the lateral repulsion between the OH adsorbed on Pt and the OH or O adsorbed on neighboring, other than Pt, late transition metal atoms. The origin of this effect was identified through a combination of experimental and theoretical methods, employing electrochemical techniques, X-ray absorption spectroscopy, and periodic, self-consistent density functional theory calculations. This new class of electrocatalysts promises to alleviate some major problems of existing fuel cell technology by simultaneously decreasing materials cost and enhancing performance.

Revised: April 7, 2011 | Published: January 20, 2007

Citation

Vukmirovic M.B., J. Zhang, K. Sasaki, A.U. Nilekar, F. Uribe, M. Mavrikakis, and R.R. Adzic, et al. 2007. Platinum Monolayer Electrocatalysts for Oxygen Reduction. Electrochimica Acta 52, no. 6:2257-2263. doi:10.1016/j.electacta.2006.05.062