Understanding support mediated activity by investigating highly active, thermally stable, silica supported gold catalysts

Journal Article · Thu Jan 01 00:00:00 EST 2009 · Journal of Catalysis

DOI:https://doi.org/10.1016/j.jcat.2008.12.005· OSTI ID:947576

Veith, Gabriel M ^[1]; Lupini, Andrew R ^[1]; Rashkeev, Sergey ^[1]; Pennycook, Stephen J ^[1]; Schwartz, Viviane ^[1]; Mullins, David R ^[1]; Dudney, Nancy J ^[1]

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1. ORNL

2.5 nm gold nanoparticles were grown on a fumed silica support using the physical vapor deposition technique magnetron sputtering. Combining electron microscopy, extended X-ray absorption fine structure (EXAFS) spectroscopy, and catalytic studies revealed that the silica supported gold catalysts are thermally stable when annealed in an oxygen containing environment up to at least 500oC. This surprising stability is attributed to the absence of residual halide impurities and a strong bond between gold and defects at the silica surface (2.7 - 3.8 eV), as estimated from density functional theory (DFT) calculations. The Au/SiO2 catalysts are slightly less active for CO oxidation than the prototypical Au/TiO2 catalysts, however they can be regenerated far more easily, fully recovering the activity of a freshly prepared catalyst after deactivation.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 947576
• Journal Information: Journal of Catalysis, Vol. 262, Issue 1; ISSN 0021-9517
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
GOLD
CATALYSTS
SILICA
CATALYST SUPPORTS
PHYSICAL VAPOR DEPOSITION
STABILITY
DENSITY FUNCTIONAL METHOD
CARBON MONOXIDE
OXIDATION
CATALYTIC EFFECTS
REGENERATION
gold
catalyst
silica
oxidation
sputtering