Abstract
The combined influence of gold content (0.5 or 4 wt. %), modifying additives (La or Ce oxides) and redox pretreatments (H 2 or O 2 ) on catalytic properties and formation of active sites of Au/TiO 2 in the selective oxidation of n-octanol under mild conditions was studied. Samples were characterized by BET, XRD, EDX, ICP, TEM, STEM-HAADF, CO 2 -TPD, H2-TPR and XPS methods. The order of catalytic activity depended on the support nature for all treated samples, as follows: Au/La 2 O 3 /TiO 2 >Au/CeO 2 /TiO 2 >Au/TiO 2 . The catalytic activity enhanced with the increase of gold loading in the samples with hydrogen pretreatment, while after the oxidative pretreatment of the catalysts the opposite dependence of the activity with the gold content was found. This catalytic behavior was explained by a change in the surface concentration of monovalent gold ions, which seemed to be the active sites. The most active catalyst, 0.5 % Au/La 2 O 3 /TiO 2 , pretreated in oxidative atmosphere, had the highest surface concentration of monovalent gold ions.
| Original language | English |
|---|---|
| Journal | ChemCatChem |
| DOIs | |
| Publication status | Published - 1 Jan 2019 |
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Keywords
- effect of pretreatments
- gold catalyst active sites
- gold loading
- n-octanol selective oxidation
- support modifiers
ASJC Scopus subject areas
- Catalysis
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry
Cite this
Green Oxidation of n-octanol on Supported Nanogold Catalysts : Formation of Gold Active Sites under Combined Effect of Gold Content, Additive Nature and Redox Pretreatment. / Pakrieva, E.; Kolobova, E.; Mamontov, G.; Bogdanchikova, N.; Farias, M. H.; Pascual, L.; Cortés Corberán, V.; Martinez Gonzalez, S.; Carabineiro, S. A.C.; Pestryakov, A.
In: ChemCatChem, 01.01.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Green Oxidation of n-octanol on Supported Nanogold Catalysts
T2 - Formation of Gold Active Sites under Combined Effect of Gold Content, Additive Nature and Redox Pretreatment
AU - Pakrieva, E.
AU - Kolobova, E.
AU - Mamontov, G.
AU - Bogdanchikova, N.
AU - Farias, M. H.
AU - Pascual, L.
AU - Cortés Corberán, V.
AU - Martinez Gonzalez, S.
AU - Carabineiro, S. A.C.
AU - Pestryakov, A.
PY - 2019/1/1
Y1 - 2019/1/1
N2 - The combined influence of gold content (0.5 or 4 wt. %), modifying additives (La or Ce oxides) and redox pretreatments (H 2 or O 2 ) on catalytic properties and formation of active sites of Au/TiO 2 in the selective oxidation of n-octanol under mild conditions was studied. Samples were characterized by BET, XRD, EDX, ICP, TEM, STEM-HAADF, CO 2 -TPD, H2-TPR and XPS methods. The order of catalytic activity depended on the support nature for all treated samples, as follows: Au/La 2 O 3 /TiO 2 >Au/CeO 2 /TiO 2 >Au/TiO 2 . The catalytic activity enhanced with the increase of gold loading in the samples with hydrogen pretreatment, while after the oxidative pretreatment of the catalysts the opposite dependence of the activity with the gold content was found. This catalytic behavior was explained by a change in the surface concentration of monovalent gold ions, which seemed to be the active sites. The most active catalyst, 0.5 % Au/La 2 O 3 /TiO 2 , pretreated in oxidative atmosphere, had the highest surface concentration of monovalent gold ions.
AB - The combined influence of gold content (0.5 or 4 wt. %), modifying additives (La or Ce oxides) and redox pretreatments (H 2 or O 2 ) on catalytic properties and formation of active sites of Au/TiO 2 in the selective oxidation of n-octanol under mild conditions was studied. Samples were characterized by BET, XRD, EDX, ICP, TEM, STEM-HAADF, CO 2 -TPD, H2-TPR and XPS methods. The order of catalytic activity depended on the support nature for all treated samples, as follows: Au/La 2 O 3 /TiO 2 >Au/CeO 2 /TiO 2 >Au/TiO 2 . The catalytic activity enhanced with the increase of gold loading in the samples with hydrogen pretreatment, while after the oxidative pretreatment of the catalysts the opposite dependence of the activity with the gold content was found. This catalytic behavior was explained by a change in the surface concentration of monovalent gold ions, which seemed to be the active sites. The most active catalyst, 0.5 % Au/La 2 O 3 /TiO 2 , pretreated in oxidative atmosphere, had the highest surface concentration of monovalent gold ions.
KW - effect of pretreatments
KW - gold catalyst active sites
KW - gold loading
KW - n-octanol selective oxidation
KW - support modifiers
UR - http://www.scopus.com/inward/record.url?scp=85061508919&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85061508919&partnerID=8YFLogxK
U2 - 10.1002/cctc.201801566
DO - 10.1002/cctc.201801566
M3 - Article
AN - SCOPUS:85061508919
JO - ChemCatChem
JF - ChemCatChem
SN - 1867-3880
ER -