Core-protected platinum monolayer shell high-stability electrocatalysts for fuel-cell cathodes.

More than skin deep: Platinum monolayers can act as shells for palladium nanoparticles to lead to electrocatalysts with high activities and an ultralow platinum content, but high platinum utilization. The stability derives from the core protecting the shell from dissolution. In fuel-cell tests, no loss of platinum was observed in 200?000 potential cycles, whereas loss of palladium was significant.

[1]  G. Kresse,et al.  Ab initio molecular dynamics for liquid metals. , 1993 .

[2]  Blöchl,et al.  Projector augmented-wave method. , 1994, Physical review. B, Condensed matter.

[3]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[4]  J. Nørskov,et al.  Improved adsorption energetics within density-functional theory using revised Perdew-Burke-Ernzerhof functionals , 1999 .

[5]  S. Brankovic,et al.  Metal monolayer deposition by replacement of metal adlayers on electrode surfaces , 2001 .

[6]  C. Liu,et al.  High-angle annular dark-field imaging of self-assembled Ge islands on Si(0 0 1). , 2001, Ultramicroscopy.

[7]  Robert M. Darling,et al.  Kinetic Model of Platinum Dissolution in PEMFCs , 2003 .

[8]  M. Miki-Yoshida,et al.  HAADF study of Au-Pt core-shell bimetallic nanoparticles , 2004 .

[9]  M. Mavrikakis,et al.  Alloy catalysts designed from first principles , 2004, Nature materials.

[10]  J. X. Wang,et al.  Kinetic Analysis of Oxygen Reduction on Pt(111) in Acid Solutions: Intrinsic Kinetic Parameters and Anion Adsorption Effects , 2004 .

[11]  Hubert A. Gasteiger,et al.  Instability of Pt ∕ C Electrocatalysts in Proton Exchange Membrane Fuel Cells A Mechanistic Investigation , 2005 .

[12]  Junliang Zhang,et al.  Controlling the catalytic activity of platinum-monolayer electrocatalysts for oxygen reduction with different substrates. , 2005, Angewandte Chemie.

[13]  H. Gasteiger,et al.  Activity benchmarks and requirements for Pt, Pt-alloy, and non-Pt oxygen reduction catalysts for PEMFCs , 2005 .

[14]  Mark K. Debe,et al.  High voltage stability of nanostructured thin film catalysts for PEM fuel cells , 2006 .

[15]  M. Łukaszewski,et al.  Dissolution of noble metals and their alloys studied by electrochemical quartz crystal microbalance , 2006 .

[16]  Andreas Menzel,et al.  Stability and Dissolution of Platinum Surfaces in Perchloric Acid , 2006 .

[17]  M. Mavrikakis,et al.  Platinum Monolayer Fuel Cell Electrocatalysts , 2007 .

[18]  Junliang Zhang,et al.  Double-trap kinetic equation for the oxygen reduction reaction on Pt(111) in acidic media. , 2007, The journal of physical chemistry. A.

[19]  Edward F. Holby,et al.  Instability of Supported Platinum Nanoparticles in Low-Temperature Fuel Cells , 2007 .

[20]  Jens K. Nørskov,et al.  Electrochemical dissolution of surface alloys in acids: Thermodynamic trends from first-principles calculations , 2007 .

[21]  K. Sasaki,et al.  Stabilization of Platinum Oxygen-Reduction Electrocatalysts Using Gold Clusters , 2007, Science.

[22]  Manos Mavrikakis,et al.  Improved oxygen reduction reactivity of platinum monolayers on transition metal surfaces , 2008 .

[23]  Lijun Wu,et al.  Oxygen reduction on well-defined core-shell nanocatalysts: particle size, facet, and Pt shell thickness effects. , 2009, Journal of the American Chemical Society.

[24]  Hubert A. Gasteiger,et al.  Platinum-Alloy Cathode Catalyst Degradation in Proton Exchange Membrane Fuel Cells: Nanometer-Scale Compositional and Morphological Changes , 2010 .