688f Dft-Based Thermodynamic Analysis of Reactivity of Ptxpdy Alloy Clusters

Sergio R. Calvo, Department of Chemical Engineering, Texas A&M University, 402 Nagle St. apt. 201, College Station, TX 77840 and Perla B. Balbuena, Chemical Engineering, Texas A&M University, DEPARTMENT OF CHEMICAL ENGINEERING, College Station, TX 77843.

Recent efforts in electrocatalysis have focused on searching new materials for the oxygen reduction reaction, especially Pt-alloys with the goals of reducing costs while increasing catalytic activity. We use the B3PW91 hybrid density functional theory to study aspects of the four electron reduction of oxygen on PtXPdY clusters (x+y =10) in various x:y ratios. A comparative thermodynamic analysis reveals that both “mixed” and “ordered” Pt3Pd7 clusters are better than Pt to catalyze this reaction. We analyze the behavior of “modified” Pd atoms and “modified” Pt atoms in various alloy environments (at the same overall composition) in comparison to those in pure Pd or Pt clusters towards the adsorption of reaction intermediates.