TY - JOUR
T1 - Nanocomposite catalysts
T2 - Dendrimer encapsulated nanoparticles immobilized in sol-gel silica
AU - Beakley, Lindsey W.
AU - Yost, Sarah E.
AU - Cheng, Raymond
AU - Chandler, Bert D.
N1 - Funding Information:
We gratefully acknowledge Research Corporation (Grant No. CC5453) for financial support of this work. Acknowledgement is made to the donors for the American Chemical Society Petroleum Research Fund for partial support of this research. We also acknowledge the National Science Foundation Major Research Instrumentation Program (Grant No. CHE-0116731) for support of the gas adsorption system.
PY - 2005/9/18
Y1 - 2005/9/18
N2 - A method for immobilizing dendrimer encapsulated nanoparticles (DENs) in a sol-gel silica matrix was developed. To evaluate timing effects for DEN addition to the sol-gel preparation, platinum DENs were added at two different times: (1) just before the condensation reactions were initialized, and (2) 24 h after initializing the condensation reactions after the sol formation but before solutions had gelled. After gellation, drying, and activation, the catalysts had similar activities for CO oxidation catalysis. The catalyst prepared after sols had formed, however, was substantially less active for toluene hydrogenation. Infrared spectroscopy of adsorbed CO indicated that this latter catalyst had fewer available surface sites and that both catalysts remained poisoned by dendrimer decomposition products after activation.
AB - A method for immobilizing dendrimer encapsulated nanoparticles (DENs) in a sol-gel silica matrix was developed. To evaluate timing effects for DEN addition to the sol-gel preparation, platinum DENs were added at two different times: (1) just before the condensation reactions were initialized, and (2) 24 h after initializing the condensation reactions after the sol formation but before solutions had gelled. After gellation, drying, and activation, the catalysts had similar activities for CO oxidation catalysis. The catalyst prepared after sols had formed, however, was substantially less active for toluene hydrogenation. Infrared spectroscopy of adsorbed CO indicated that this latter catalyst had fewer available surface sites and that both catalysts remained poisoned by dendrimer decomposition products after activation.
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U2 - 10.1016/j.apcata.2005.05.049
DO - 10.1016/j.apcata.2005.05.049
M3 - Article
AN - SCOPUS:24144439076
VL - 292
SP - 124
EP - 129
JO - Applied Catalysis A: General
JF - Applied Catalysis A: General
SN - 0926-860X
IS - 1-2
ER -