In situ studies of titania-supported Au shell-Pd core nanoparticles for the selective aerobic oxidation of crotyl alcohol

Adam F. Lee, Christine V. Ellis, Karen Wilson, Nicole S. Hondow

Research output: Contribution to journalArticle

Abstract

The thermal evolution of titania-supported Au shell–Pd core bimetallic nanoparticles, prepared via colloidal routes, has been investigated by in situ XPS, DRIFTS, EXAFS and XRD and ex situ HRTEM. As-prepared nanoparticles are terminated by a thin (∼5 layer) Au shell, encapsulating approximately 20 nm diameter cuboctahedral palladium cores, with the ensemble stabilised by citrate ligands. The net gold composition was 40 atom%. Annealing in vacuo or under inert atmosphere rapidly pyrolyses the citrate ligands, but induces only limited Au/Pd intermixing and particle growth <300 °C. Higher temperatures promote more dramatic alloying, accompanied by significant sintering and surface roughening. These changes are mirrored by the nanoparticle catalysed liquid phase selective aerobic oxidation of crotyl alcohol to crotonaldehyde; palladium surface segregation enhances both activity and selectivity, with the most active surface alloy attainable containing ∼40 atom% Au.
Original languageEnglish
Pages (from-to)243-249
Number of pages7
JournalCatalysis Today
Volume157
Issue number1-4
Early online date23 May 2010
DOIs
Publication statusPublished - 17 Nov 2010
Event6th World Congress on Oxidation Catalysis - Lille, France
Duration: 5 Jul 200910 Jul 2009

Fingerprint

2-butenal
Alcohols
Titanium
Palladium
Nanoparticles
Citric Acid
Oxidation
Ligands
Surface segregation
Atoms
Alloying
Gold
Pyrolysis
Sintering
X ray photoelectron spectroscopy
Annealing
Liquids
Chemical analysis
titanium dioxide
crotonyl alcohol

Bibliographical note

We thank the Engineering and Physical Sciences Research Council for financial support (EP/E046754/1 and EP/G007594/1) and the award of a Leadership Fellowship (A.F.L.) and studentship (C.V.E.). Electron microscopy access was provided through the Leeds EPSRC Nanoscience and Nanotechnology Research Equipment Facility (LENNF) (EP/F056311/1). We also thank Syngenta for additional studentship support and Mr. L. Dingwall (York Chemistry) and Dr. I. Harvey for assistance with DRIFTS and EXAFS measurements, respectively.

Keywords

  • bimetallic
  • gold
  • palladium
  • XPS
  • oxidation
  • in situ

Cite this

Lee, Adam F. ; Ellis, Christine V. ; Wilson, Karen ; Hondow, Nicole S. / In situ studies of titania-supported Au shell-Pd core nanoparticles for the selective aerobic oxidation of crotyl alcohol. In: Catalysis Today. 2010 ; Vol. 157, No. 1-4. pp. 243-249.
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In situ studies of titania-supported Au shell-Pd core nanoparticles for the selective aerobic oxidation of crotyl alcohol. / Lee, Adam F.; Ellis, Christine V.; Wilson, Karen; Hondow, Nicole S.

In: Catalysis Today, Vol. 157, No. 1-4, 17.11.2010, p. 243-249.

Research output: Contribution to journalArticle

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