| Literature DB >> 27034369 |
María Escudero-Escribano1, Paolo Malacrida2, Martin H Hansen3, Ulrik G Vej-Hansen4, Amado Velázquez-Palenzuela2, Vladimir Tripkovic5, Jakob Schiøtz4, Jan Rossmeisl3, Ifan E L Stephens6, Ib Chorkendorff7.
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.Entities:
Year: 2016 PMID： 27034369 DOI： 10.1126/science.aad8892
Source DB: PubMed Journal: Science ISSN： 0036-8075 Impact factor: 47.728