Modification of Au/TiO2 nanosystems by SiO2 monolayers: Toward the control of the catalyst activity and stability

Sergey Rashkeev, Sheng Dai, Steven H. Overbury

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

The activity and stability of Au/TiO2 catalysts depend on several different factors such as the anchoring strength of the Au particles at the TiO2 surface, the particle sintering, and the surface mobility of individual gold atoms and/or gold particles. Au/TiO2 catalysts can be made resistant to sintering by atomic layer deposition (ALD) of a layer of SiO2 onto the catalysts. In this study, first-principles density-functional calculations are used to investigate how the stability of Au nanoparticles is modified when a partial monolayer of SiO2 is deposited on a Au/TiO2 catalyst. We find that SiO2 structures deposited on a pure TiO2 substrate exhibit lattice-mismatch instabilities that result in the formation of additional strong anchoring sites for Au atoms/nanoparticles. An atomic-scale roughness introduced by a partial monolayer of SiO2 can slow the atomic surface diffusion and inhibit Au nanoparticle growth/sintering, in agreement with previous experimental results.

Original languageEnglish
Pages (from-to)2996-3002
Number of pages7
JournalJournal of Physical Chemistry C
Volume114
Issue number7
DOIs
Publication statusPublished - 25 Feb 2010
Externally publishedYes

Fingerprint

Nanosystems
Monolayers
Catalyst activity
catalysts
sintering
Catalysts
Sintering
Nanoparticles
Gold
nanoparticles
gold
Atoms
Lattice mismatch
Atomic layer deposition
Surface diffusion
atomic layer epitaxy
surface diffusion
Density functional theory
atoms
roughness

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Electronic, Optical and Magnetic Materials
  • Surfaces, Coatings and Films
  • Energy(all)

Cite this

Modification of Au/TiO2 nanosystems by SiO2 monolayers : Toward the control of the catalyst activity and stability. / Rashkeev, Sergey; Dai, Sheng; Overbury, Steven H.

In: Journal of Physical Chemistry C, Vol. 114, No. 7, 25.02.2010, p. 2996-3002.

Research output: Contribution to journalArticle

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