Shape-Controlled Bimetallic Nanocatalysts in Fuel Cells Synthesis and Electrocatalytic Studies

Shape-Controlled Bimetallic Nanocatalysts in Fuel Cells Synthesis and Electrocatalytic Studies 

Many types of bimetallic catalysts have been used to investigate electrocatalytic performance, including single-crystal surfaces [6], sputtered particles [5,7], carbon-supported catalysts fabricated by impregnation reduction, and colloidal nanocrystals (NCs). Bimetallic single crystals are indispensable when investigating facet-specific electrocatalytic properties sputtered bimetallic particles can be used as model catalysts with a clean surface to study the effect of composition on 

Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Rare Earth Materials Chemistry and Applications, PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China e-mail ywzhang pku.edu.cn 

Park (ed.). Current Trends of Surface Science and Catalysis, 121 

According to the function of two compositions of BMNCs in the electrocatalytic reaction, BMNCs can be divided into mono-functional catalysts and bi-functional catalysts. In mono-functional catalysts, reagents are only adsorbed on one kind of metal atoms in bi-functional catalysts, both kinds of metal atoms on the surface serve as adsorption sites for different reagents. The alloy BMNCs of Pt and early transition metals as ORR catalysts are mono-functional catalysts, in which reagent and intermediates are only adsorbed on the Pt sites and the early transition metals are introduced to modulate the electronic stmcture of the Pt and improve the ORR activity [5, 6, 8]. Pt-Ru catalysts used for methanol electro-oxidation, however, are considered as bi-functional catalysts where Pt atoms serve as the adsorption sites of the C-species and Ru atoms serve as the adsorption sites of the 0-species [9, 10]. If BMNCs are to serve as bi-functional catalysts, the synthetic approach should be specially designed to optimize the ratio of the exposed sites of each of the two metal atoms. 

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