Details

Autor(en) / Beteiligte

• Chen, Chen
• Kang, Yijin
• Huo, Ziyang
• Zhu, Zhongwei
• Huang, Wenyu
• Xin, Huolin L.
• Snyder, Joshua D.
• Li, Dongguo
• Herron, Jeffrey A.
• Mavrikakis, Manos
• Chi, Miaofang
• More, Karren L.
• Li, Yadong
• Markovic, Nenad M.
• Somorjai, Gabor A.
• Yang, Peidong
• Stamenkovic, Vojislav R.

Titel

Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces

Ist Teil von

• Science (American Association for the Advancement of Science), 2014-03, Vol.343 (6177), p.1339-1343

Ort / Verlag

United States: American Association for the Advancement of Science

Erscheinungsjahr

2014

Quelle

American Association for the Advancement of Science

Beschreibungen/Notizen

• Control of structure at the atomic level can precisely and effectively tune catalytic properties of materials, enabling enhancement in both activity and durability. We synthesized a highly active and durable class of electrocatalysts by exploiting the structural evolution of platinum-nickel (Pt-Ni) bimetallic nanocrystals. The starting material, crystalline PtNi3 polyhedra, transforms in solution by interior erosion into Pt3Ni nanoframes with surfaces that offer three-dimensional molecular accessibility. The edges of the Pt-rich PtNi3 polyhedra are maintained in the final Pt3Ni nanoframes. Both the interior and exterior catalytic surfaces of this open-framework structure are composed of the nanosegregated Pt-skin structure, which exhibits enhanced oxygen reduction reaction (ORR) activity. The Pt3Ni nanoframe catalysts achieved a factor of 36 enhancement in mass activity and a factor of 22 enhancement in specific activity, respectively, for this reaction (relative to state-of-the-art platinum-carbon catalysts) during prolonged exposure to reaction conditions.