Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction

Maria Escudero Escribano, Paolo Malacrida, Martin Hangaard Hansen, Ulrik Grønbjerg Vej-Hansen, Amado Andres Velazquez-Palenzuela, Vladimir Tripkovic, Jakob Schiøtz, Jan Rossmeisl, Ifan E. L. Stephens, Ib Chorkendorff

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

The high platinum loadings required to compensate for the slow kinetics of the oxygen reduction reaction (ORR) impede the widespread uptake of low-temperature fuel cells in automotive vehicles. We have studied the ORR on eight platinum (Pt)–lanthanide and Pt-alkaline earth electrodes, Pt5M, where M is lanthanum, cerium, samarium, gadolinium, terbium, dysprosium, thulium, or calcium. The materials are among the most active polycrystalline Pt-based catalysts reported, presenting activity enhancement by a factor of 3 to 6 over Pt. The active phase consists of a Pt overlayer formed by acid leaching. The ORR activity versus the bulk lattice parameter follows a high peaked “volcano” relation. We demonstrate how the lanthanide contraction can be used to control strain effects and tune the activity, stability, and reactivity of these materials.
Original languageEnglish
JournalScience
Volume352
Issue number6281
Pages (from-to)73-76
Number of pages4
ISSN0036-8075
DOIs
Publication statusPublished - 2016

Keywords

  • Reports
  • CHEMISTRY

Cite this

Escribano, M. E., Malacrida, P., Hansen, M. H., Vej-Hansen, U. G., Velazquez-Palenzuela, A. A., Tripkovic, V., Schiøtz, J., Rossmeisl, J., Stephens, I. E. L., & Chorkendorff, I. (2016). Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction. Science, 352(6281), 73-76. https://doi.org/10.1126/science.aad8892