Home > Research > Publications & Outputs > Oxygen reduction on structurally well defined, ...

Links

Text available via DOI:

View graph of relations

Oxygen reduction on structurally well defined, bimetallic PtRu surfaces: monolayer PtxRu1-x/Ru(0001) surface alloys versus Pt film covered Ru(0001)

Research output: Contribution to journalJournal articlepeer-review

Published
Close
<mark>Journal publication date</mark>02/2014
<mark>Journal</mark>Topics in Catalysis
Issue number1-4
Volume57
Number of pages14
Pages (from-to)222-235
Publication StatusPublished
Early online date23/10/13
<mark>Original language</mark>English

Abstract

The electrocatalytic activity of different, structurally well defined bimetallic PtRu surfaces in the oxygen reduction reaction was investigated by a combination of scanning tunnelling microscopy and electrochemical measurements performed under controlled mass transport conditions in a flow cell. We compare the effect of pseudomorphic Pt cover layers, mimicking the situation in a core-shell Pt/Ru nanoparticle, and of mixed PtxRu1-x monolayer surface alloys, reflecting the situation in an alloyed nanoparticle. The results unambiguously demonstrate that these bimetallic surfaces can reach activities well in excess of that of Pt(111), both for the film surfaces and the surface alloys, by optimizing the Pt surface content (surface alloys) or the Pt film thickness (film surfaces). The results are compared with simulated kinetic current-potential profiles based on existent density functional theory calculations (Greeley and Norskov, J Phys Chem C 113:4932, 2009; Lischka et al., Electrochim Acta 52:2219, 2007) revealing very good agreement in trends. Potential and limits of this approach are discussed.