Journal article
Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction
Department of Physics, Technical University of Denmark1
Surface Physics and Catalysis, Department of Physics, Technical University of Denmark2
Center for Individual Nanoparticle Functionality, Centers, Technical University of Denmark3
Center for Atomic-scale Materials Design, Centers, Technical University of Denmark4
Computational Atomic-scale Materials Design, Department of Physics, Technical University of Denmark5
Department of Energy Conversion and Storage, Technical University of Denmark6
Atomic Scale Materials Modelling, Department of Energy Conversion and Storage, Technical University of Denmark7
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.
Language: | English |
---|---|
Publisher: | American Association for the Advancement of Science |
Year: | 2016 |
Pages: | 73-76 |
ISSN: | 10959203 and 00368075 |
Types: | Journal article |
DOI: | 10.1126/science.aad8892 |
ORCIDs: | Hansen, Martin Hangaard , Vej-Hansen, Ulrik Grønbjerg , Velazquez-Palenzuela, Amado Andres , Schiøtz, Jakob , Stephens, Ifan E. L. , Chorkendorff, Ib and 0000-0001-7749-6567 |