Small palladium islands embedded in palladium-tungsten bimetallic nanoparticles form catalytic hotspots for oxygen reduction
Artikel i vetenskaplig tidskrift, 2014

The sluggish kinetics of the oxygen reduction reaction at the cathode side of proton exchange membrane fuel cells is one major technical challenge for realizing sustainable solutions for the transportation sector. Finding efficient yet cheap electrocatalysts to speed up this reaction therefore motivates researchers all over the world. Here we demonstrate an efficient synthesis of palladium-tungsten bimetallic nanoparticles supported on ordered mesoporous carbon. Despite a very low percentage of noble metal (palladium: tungsten = 1:8), the hybrid catalyst material exhibits a performance equal to commercial 60% platinum/Vulcan for the oxygen reduction process. The high catalytic efficiency is explained by the formation of small palladium islands embedded at the surface of the palladium-tungsten bimetallic nanoparticles, generating catalytic hotspots. The palladium islands are similar to 1 nm in diameter, and contain 10-20 palladium atoms that are segregated at the surface. Our results may provide insight into the formation, stabilization and performance of bimetallic nanoparticles for catalytic reactions.

Författare

G. Z. Hu

Umeå universitet

Florian Nitze

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

E. Gracia-Espino

Umeå universitet

J. Y. Ma

Shanghai Institute of Applied Physics, Chinese Academy of Sciences

H. R. Barzegar

Umeå universitet

T. Sharifi

Umeå universitet

X. E. Jia

Umeå universitet

A. Shchukarev

Umeå universitet

L. Lu

Xi'an Jiaotong University

C. S. Ma

Xi'an Jiaotong University

G. Yang

Xi'an Jiaotong University

T. Wagberg

Umeå universitet

Nature Communications

2041-1723 (ISSN)

Vol. 5 Art. no. 5253- 5253

Ämneskategorier

Övrig annan teknik

DOI

10.1038/ncomms6253