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Title: In-situ X-ray Absorption Spectroscopy of Supported Ru Catalysts in the Aqueous Phase

Abstract

The size of supported Ru metal particles on various supports was monitored by in situ X-ray absorption spectroscopy under aqueous phase conditions typical of biomass conversion reactions. In particular, Ru/{gamma}-Al{sub 2}O{sub 3}, Ru/C, Ru/TiO{sub 2}, and Ru/SiO{sub 2} were evaluated at the Ru K edge at 473 K in neutral water and 0.4 M NaOH. The as-prepared samples exposed to air contained oxidized Ru that was subsequently reduced by H{sub 2}-saturated water solution. Significant growth of the metal particles was observed on the Ru/{gamma}-Al{sub 2}O{sub 3} and Ru/SiO{sub 2} samples during the aqueous treatments, whereas the Ru/TiO{sub 2} and Ru/C samples were quite stable under the conditions used here. Results from post-treatment X-ray diffraction and surface area analysis revealed major structural changes of the alumina and silica supports. The structural stability of the carbon and titania account for the lack of metal particle growth on those supports. Because a reference Pt/C catalyst revealed metal particle growth under the same conditions, the results for the Ru/C cannot be generalized to other carbon-supported catalysts and underscores the importance of in situ characterization for heterogeneous catalysts in the aqueous phase.

Authors:
; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
929894
Report Number(s):
BNL-80476-2008-JA
Journal ID: ISSN 0897-4756; CMATEX; TRN: US200822%%1073
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chemistry of Materials; Journal Volume: 19; Journal Issue: 14
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; ABSORPTION SPECTROSCOPY; AQUEOUS SOLUTIONS; BIOMASS; CARBON; CATALYSTS; CONVERSION; GROWTH; METALS; PARTICLES; SILICA; SIZE; STABILITY; SURFACE AREA; X-RAY DIFFRACTION; national synchrotron light source

Citation Formats

Ketchie,W., Maris, E., and Davis, R. In-situ X-ray Absorption Spectroscopy of Supported Ru Catalysts in the Aqueous Phase. United States: N. p., 2007. Web. doi:10.1021/cm0702868.
Ketchie,W., Maris, E., & Davis, R. In-situ X-ray Absorption Spectroscopy of Supported Ru Catalysts in the Aqueous Phase. United States. doi:10.1021/cm0702868.
Ketchie,W., Maris, E., and Davis, R. Mon . "In-situ X-ray Absorption Spectroscopy of Supported Ru Catalysts in the Aqueous Phase". United States. doi:10.1021/cm0702868.
@article{osti_929894,
title = {In-situ X-ray Absorption Spectroscopy of Supported Ru Catalysts in the Aqueous Phase},
author = {Ketchie,W. and Maris, E. and Davis, R.},
abstractNote = {The size of supported Ru metal particles on various supports was monitored by in situ X-ray absorption spectroscopy under aqueous phase conditions typical of biomass conversion reactions. In particular, Ru/{gamma}-Al{sub 2}O{sub 3}, Ru/C, Ru/TiO{sub 2}, and Ru/SiO{sub 2} were evaluated at the Ru K edge at 473 K in neutral water and 0.4 M NaOH. The as-prepared samples exposed to air contained oxidized Ru that was subsequently reduced by H{sub 2}-saturated water solution. Significant growth of the metal particles was observed on the Ru/{gamma}-Al{sub 2}O{sub 3} and Ru/SiO{sub 2} samples during the aqueous treatments, whereas the Ru/TiO{sub 2} and Ru/C samples were quite stable under the conditions used here. Results from post-treatment X-ray diffraction and surface area analysis revealed major structural changes of the alumina and silica supports. The structural stability of the carbon and titania account for the lack of metal particle growth on those supports. Because a reference Pt/C catalyst revealed metal particle growth under the same conditions, the results for the Ru/C cannot be generalized to other carbon-supported catalysts and underscores the importance of in situ characterization for heterogeneous catalysts in the aqueous phase.},
doi = {10.1021/cm0702868},
journal = {Chemistry of Materials},
number = 14,
volume = 19,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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