Au/PO43-/TiO2 and PO43-/Au/TiO2 catalysts for CO oxidation: effect of synthesis details on catalytic performance

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Applied Catalysis A

DOI:https://doi.org/10.1016/j.apcata.2007.05.019· OSTI ID:931729

Ma, Zhen ^[1]; Dai, Sheng ^[1]

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1. ORNL

Supported gold catalysts are active for CO oxidation, but the high-temperature deactivation is a shortcoming that may constrain their applications. Herein, we attempted to address this problem by using phosphate-doped Au/TiO{sub 2} synthesized via two routes. In route I, Au/PO{sub 4}{sup 3-}/TiO{sub 2} catalysts were prepared by treating TiO{sub 2} (Degussa P25) with diluted H{sub 3}PO{sub 4}, followed by loading gold via deposition-precipitation. In route II, PO{sub 4}{sup 3-}/Au/TiO{sub 2} catalysts were prepared by treating H{sub 2}-reduced Au/TiO{sub 2} with diluted H{sub 3}PO{sub 4}. These catalysts were systematically pretreated at 200 or 500 C before reaction testing. The overall CO conversion on 200 C-pretreated Au/PO43-/TiO2 or PO43-/Au/TiO2 was always lower than that on 200 C-pretreated Au/TiO2. However, the advantage of the phosphate addition became apparent after thermal treatment at a higher temperature. Both Au/PO43-/TiO2 and PO43-/Au/TiO2 pretreated at 500 C retained significant activities at room temperature, whereas 500 C-pretreated Au/TiO2 lost its activity. Control experiments and catalyst characterization were performed to investigate the impact of synthesis details on catalytic performance.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 931729
• Journal Information: Applied Catalysis A, Journal Name: Applied Catalysis A Journal Issue: 2 Vol. 327
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CARBON MONOXIDE
CATALYST SUPPORTS
CATALYSTS
CATALYTIC EFFECTS
DEACTIVATION
GOLD
OXIDATION
PHOSPHATES
SYNTHESIS
TITANIUM OXIDES