Francisco J Perez-Alonso

Publications (3)36.82 Total impact

• Article: Design of an Active Site towards Optimal Electrocatalysis: Overlayers, Surface Alloys and Near-Surface Alloys of Cu/Pt(111).

  Aliaksandr S Bandarenka, Ana Sofia Varela, Mohammedreza Karamad, Federico Calle-Vallejo, Lone Bech, Francisco J Perez-Alonso, Jan Rossmeisl, Ifan E L Stephens, Ib Chorkendorff
  [show abstract] [hide abstract]
  ABSTRACT: I could never be without Cu: An active site has been designed for the catalysis of CO electroxidation. This was achieved by incorporating submonolayer amounts of Cu (orange shperes) into a single crystal of Pt (gray spheres). The electrochemical reactivity of this surface was highly sensitive to the exact position of Cu.
  Angewandte Chemie International Edition 10/2012; · 13.45 Impact Factor
• Article: The effect of size on the oxygen electroreduction activity of mass-selected platinum nanoparticles.

  Francisco J Perez-Alonso, David N McCarthy, Anders Nierhoff, Patricia Hernandez-Fernandez, Christian Strebel, Ifan E L Stephens, Jane H Nielsen, Ib Chorkendorff
  [show abstract] [hide abstract]
  ABSTRACT: A matter of size: The particle size effect on the activity of the oxygen reduction reaction of size-selected platinum clusters was studied. The ORR activity decreased with decreasing Pt nanoparticle size, corresponding to a decrease in the fraction of terraces on the surfaces of the Pt nanoparticles (j(k) =kinetic current density, see picture).
  Angewandte Chemie International Edition 03/2012; 51(19):4641-3. · 13.45 Impact Factor
• Article: Tuning the activity of Pt(111) for oxygen electroreduction by subsurface alloying.

  Ifan E L Stephens, Alexander S Bondarenko, Francisco J Perez-Alonso, Federico Calle-Vallejo, Lone Bech, Tobias P Johansson, Anders K Jepsen, Rasmus Frydendal, Brian P Knudsen, Jan Rossmeisl, Ib Chorkendorff
  [show abstract] [hide abstract]
  ABSTRACT: To enable the development of low temperature fuel cells, significant improvements are required to the efficiency of the Pt electrocatalysts at the cathode, where oxygen reduction takes place. Herein, we study the effect of subsurface solute metals on the reactivity of Pt, using a Cu/Pt(111) near-surface alloy. Our investigations incorporate electrochemical measurements, ultrahigh vacuum experiments, and density functional theory. Changes to the OH binding energy, ΔE(OH), were monitored in situ and adjusted continuously through the subsurface Cu coverage. The incorporation of submonolayer quantities of Cu into Pt(111) resulted in an 8-fold improvement in oxygen reduction activity. The most optimal catalyst for oxygen reduction has an ΔE(OH) ≈ 0.1 eV weaker than that of pure Pt, validating earlier theoretical predictions.
  Journal of the American Chemical Society 03/2011; 133(14):5485-91. · 9.91 Impact Factor