PdCu Nanoalloy Electrocatalysts in Oxygen Reduction Reaction: Role of Composition and Phase State in Catalytic Synergy

• DOI: 10.1021/acsami.5b08478
• Publication Date: 2015-11-16T19:27:17Z
• Authors: Jinfang Wu; Shiyao Shan; Jin Luo; Pharrah Joseph; Valeri Petkov; Chuan-Jian Zhong
• Keywords: 02 engineering and technology; 0210 nano-technology

The catalytic synergy of nanoalloy catalysts depends on the nanoscale size, composition, phase state, and surface properties. This report describes findings an investigation their roles in enhancement electrocatalytic activity PdCu alloy nanoparticle for oxygen reduction reaction (ORR). PdnCu100–n nanoalloys with controlled composition subtle differences size state were synthesized by two different wet chemical methods. Detailed electrochemical characterization was performed to determine properties activities. atomic-scale structures these also characterized high-energy synchrotron X-ray diffraction coupled atomic pair distribution function analysis. stability shown depend structure. With from both methods, a maximum ORR revealed at Pd/Cu ratio close 50:50. Structurally, Pd50Cu50 feature mixed consisting chemically ordered (body-centered cubic type) disordered (face-centered domains. phase-segregated structure is change single upon potential cycling condition. While Cu dissolution occurred synthesis single-phase character found exhibit tendency much greater than that segregation. Analysis results, along theoretical modeling based density functional theory calculation, has provided new insights correlation between catalyst structures.