title: Highly stable Pt monolayer on PdAu nanoparticle electrocatalysts for the oxygen reduction reaction.
abstract: Stability is one of the main requirements for commercializing fuel cell electrocatalysts for automotive applications. Platinum is the best-known catalyst for oxygen reduction in cathodes, but it undergoes dissolution during potential changes while driving electric vehicles, thus hampering commercial adoption. Here we report a new class of highly stable, active electrocatalysts comprising platinum monolayers on palladium-gold alloy nanoparticles. In fuel-cell tests, this electrocatalyst with its ultra-low platinum content showed minimal degradation in activity over 100,000 cycles between potentials 0.6 and 1.0 V. Under more severe conditions with a potential range of 0.6-1.4 V, again we registered no marked losses in platinum and gold despite the dissolution of palladium. These data coupled with theoretical analyses demonstrated that adding a small amount of gold to palladium and forming highly uniform nanoparticle cores make the platinum monolayer electrocatalyst significantly tolerant and very promising for the automotive application of fuel cells.
authors.affiliation: Chemistry Department, Brookhaven National Laboratory, Building 555, Upton, New York 11973-5000, USA. ksasaki@bnl.gov
authors.forename: Kotaro
authors.initials: K
authors.lastname: Sasaki
authors.forename: Hideo
authors.initials: H
authors.lastname: Naohara
authors.forename: Yongman
authors.initials: Y
authors.lastname: Choi
authors.forename: Yun
authors.initials: Y
authors.lastname: Cai
authors.forename: Wei-Fu
authors.initials: WF
authors.lastname: Chen
authors.forename: Ping
authors.initials: P
authors.lastname: Liu
authors.forename: Radoslav R
authors.initials: RR
authors.lastname: Adzic
mesh_terms: D002384:Catalysis; D004563:Electrochemistry; D006046:Gold / Q000737:chemistry*; D036103:Nanotechnology; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*
chemical_list: D010984:Platinum; D010165:Palladium; D006046:Gold