Jump to main content
Jump to site search


Nanoscale Mechanism of the Stabilization of Nanoporous Gold by Alloyed Platinum

Abstract

Nanoporous gold (NPG) is usually made by electrochemical dealloying of Ag from binary AgAu alloys. The resulting nanoscale ligaments are not very stable, and tend to coarsen with time by surface self-diffusion, especially in electrolyte, which may lead to inferior electrocatalytic properties. Addition of a small amount of Pt to the precursor alloy is known to refine and stabilize the nanoporous product (NPG-Pt). However, the mechanisms by which Pt serves to refine the microstructure remain poorly understood. The present study aims to expand our knowledge of the role of Pt by examining NPG-Pt at atomic resolution with Atom Probe Tomography (APT), as well as by aberration-corrected Transmission Electron Microscopy. Atomic level observation of Pt enrichment on ligament surfaces sheds light on the underlying mechanisms that give rise to Pt’s refining effect. Owing to improved Ag retention with higher Pt content, NPG-Pt1 was shown to have the highest surface area-to-volume ratio, compared to NPG-Pt3. Quantitative estimates reveal up to 5-fold enrichment of Pt at nanoligament surfaces, compared to the precursor content, in NPG-Pt. The interface between the dealloyed layer and the substrate was captured by APT, for the first time. The findings of this investigation add insight into the functionality of NPG-Pt and its prospective catalytic performance.

Back to tab navigation

Supplementary files

Publication details

The article was received on 03 Nov 2017, accepted on 11 Feb 2018 and first published on 12 Feb 2018


Article type: Paper
DOI: 10.1039/C7NR08206A
Citation: Nanoscale, 2018, Accepted Manuscript
  •   Request permissions

    Nanoscale Mechanism of the Stabilization of Nanoporous Gold by Alloyed Platinum

    A. El-Zoka, B. Langelier, A. Korinek, G. Botton and R. Newman, Nanoscale, 2018, Accepted Manuscript , DOI: 10.1039/C7NR08206A

Search articles by author

Spotlight

Advertisements