title: Controlled synthesis of Pd-Pt alloy hollow nanostructures with enhanced catalytic activities for oxygen reduction.
abstract: Pd-Pt alloy nanocrystals (NCs) with hollow structures such as nanocages with porous walls and dendritic hollow structures and Pd@Pt core-shell dendritic NCs could be selectively synthesized by a galvanic replacement method with uniform Pd octahedral and cubic NCs as sacrificial templates. Fine control over the degree of galvanic replacement of Pd with Pt allowed the production of Pd-Pt NCs with distinctly different morphologies. The synthesized hollow NCs exhibited considerably enhanced oxygen reduction activities compared to those of Pd@Pt core-shell NCs and a commercial Pt/C catalyst, and their electrocatalytic activities were highly dependent on their morphologies. The Pd-Pt nanocages prepared from octahedral Pd NC templates exhibited the largest improvement in catalytic performance. We expect that the present work will provide a promising strategy for the development of efficient oxygen reduction electrocatalysts and can also be extended to the preparation of other hybrid or hetero-nanostructures with desirable morphologies and functions.
authors.affiliation: Department of Chemistry and KI for the NanoCentury, KAIST, Daejeon 305-701, Korea.
authors.forename: Jong Wook
authors.initials: JW
authors.lastname: Hong
authors.forename: Shin Wook
authors.initials: SW
authors.lastname: Kang
authors.forename: Bu-Seo
authors.initials: BS
authors.lastname: Choi
authors.forename: Dongheun
authors.initials: D
authors.lastname: Kim
authors.forename: Sang Bok
authors.initials: SB
authors.lastname: Lee
authors.forename: Sang Woo
authors.initials: SW
authors.lastname: Han
mesh_terms: D000497:Alloys / Q000737:chemistry*; D002384:Catalysis; D004563:Electrochemistry; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D010165:Palladium / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D000497:Alloys; D014867:Water; D010984:Platinum; D010165:Palladium; D010100:Oxygen