Open Access
Nano Express

Nanoscale Research Letters

, 2:12

Nanocrystal and surface alloy properties of bimetallic Gold-Platinum nanoparticles

Authors

  • Derrick Mott
    • Department of ChemistryState University of New York at Binghamton
  • Jin Luo
    • Department of ChemistryState University of New York at Binghamton
  • Andrew Smith
    • Department of ChemistryState University of New York at Binghamton
  • Peter N. Njoki
    • Department of ChemistryState University of New York at Binghamton
  • Lingyan Wang
    • Department of ChemistryState University of New York at Binghamton
  • Chuan-Jian Zhong
    • Department of ChemistryState University of New York at Binghamton

DOI: 10.1007/s11671-006-9022-8

Abstract

We report on the correlation between the nanocrystal and surface alloy properties with the bimetallic composition of gold-platinum(AuPt) nanoparticles. The fundamental understanding of whether the AuPt nanocrystal core is alloyed or phase-segregated and how the surface binding properties are correlated with the nanoscale bimetallic properties is important not only for the exploitation of catalytic activity of the nanoscale bimetallic catalysts, but also to the general exploration of the surface or interfacial reactivities of bimetallic or multimetallic nanoparticles. The AuPt nanoparticles are shown to exhibit not only single-phase alloy character in the nanocrystal, but also bimetallic alloy property on the surface. The nanocrystal and surface alloy properties are directly correlated with the bimetallic composition. The FTIR probing of CO adsorption on the bimetallic nanoparticles supported on silica reveals that the surface binding sites are dependent on the bimetallic composition. The analysis of this dependence further led to the conclusion that the relative Au-atop and Pt-atop sites for the linear CO adsorption on the nanoparticle surface are not only correlated with the bimetallic composition, but also with the electronic effect as a result of the d-band shift of Pt in the bimetallic nanocrystals, which is the first demonstration of the nanoscale core-surface property correlation for the bimetallic nanoparticles over a wide range of bimetallic composition.

Keywords

Gold-Platinum nanoparticles Nanocrystal alloy Surface binding sites Bimetallic composition

[119]

(See supplementary material 1)

Acknowledgments

This work was supported in part by the National Science Foundation (CHE 0316322), the Petroleum Research Fund administered by the American Chemical Society (40253-AC5M), and the GROW Program of World Gold Council. We also thank Dr. H. R. Naslund for DCP-AES analysis, and Dr. V. Petkov for XRD analysis.

Supplementary material

11671_2006_9022_MOESM1_ESM.doc (117 kb)
Electronic Supplementary Material: Supplementary material is available to authorised users in the online version of this article athttp://dx.doi.org/10.1007/s11671-006-9022-8 (DOC 117 KB)

Copyright information

© to the authors 2006