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Indexed by:期刊论文

Date of Publication:2012-08-01

Journal:MICROPOROUS AND MESOPOROUS MATERIALS

Included Journals:SCIE、EI

Volume:158

Page Number:7-12

ISSN No.:1387-1811

Key Words:Porous silica; Au/CeO2/SiO2; CO oxidation; HMS

Abstract:Porous silica with different nanostructures, namely two-dimensional hexagonal SBA-15, three-dimensional cubic KIT-6 and hierarchical monolith silica (HMS), were used as supports to fabricate gold catalysts using a liquid-phase deposition-precipitation method. Pre-loading of ceria on porous silica can significantly improve the dispersion of the subsequently introduced gold nanoparticles and the catalytic activity of the final composite (Au/CeO2/SiO2) catalysts in CO oxidation. The composite catalysts were characterized by N-2 adsorption, X-ray diffraction. The results indicate that different nanostructures of silica imposed significant influence on the catalytic activity of Au/CeO2/SiO2 catalysts. Gold catalyst supported on HMS exhibited the highest activity for the conversion of CO to CO2 with a complete conversion (T-100%) at a temperature of 60 degrees C and at a space velocity of 80,000 mL g(cat)(-1) h(-1), whereas T-100% shifted to 120-130 degrees C for SBA-15 and KIT-6 supported gold catalysts. (C) 2012 Elsevier Inc. All rights reserved.