Co-ordinatively Unsaturated Al3+ Centers as Binding Sites for Active Catalyst Phases of Platinum on -Al2O3
Abstract
In many heterogeneous catalysts, the interaction of metal particles with their oxide support can alter the electronic properties of the metal and can play a critical role in determining particle morphology and maintaining dispersion. We used a combination of ultrahigh magnetic field, solid-state magic-angle spinning nuclear magnetic resonance spectroscopy, and high-angle annular dark-field scanning transmission electron microscopy coupled with density functional theory calculations to reveal the nature of anchoring sites of a catalytically active phase of platinum on the surface of a {gamma}-Al{sub 2}O{sub 3} catalyst support material. The results obtained show that coordinatively unsaturated pentacoordinate Al{sup 3+} (Al{sub penta}{sup 3+}) centers present on the (100) facets of the {gamma}-Al{sub 2}O{sub 3} surface are anchoring Pt. At low loadings, the active catalytic phase is atomically dispersed on the support surface (Pt/Al{sub penta}{sup 3+} = 1), whereas two-dimensional Pt rafts form at higher coverages.
- Authors:
-
- Pacific Northwest National Laboratory (PNNL)
- ORNL
- Publication Date:
- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Temperature Materials Lab. (HTML)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- OSTI Identifier:
- 982389
- DOE Contract Number:
- DE-AC05-00OR22725
- Resource Type:
- Journal Article
- Journal Name:
- Science
- Additional Journal Information:
- Journal Volume: 325; Journal Issue: 5948; Journal ID: ISSN 0036-8075
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CATALYST SUPPORTS; CATALYSTS; ALUMINIUM OXIDES; PLATINUM; SURFACE PROPERTIES; DENSITY FUNCTIONAL METHOD; NUCLEAR MAGNETIC RESONANCE; TRANSMISSION ELECTRON MICROSCOPY; SCANNING ELECTRON MICROSCOPY; alumina; pentacoordinate; Al3+ binding sites; catalyst; barium oxide; NMR; STEM
Citation Formats
Kwak, Ja Hun, Hu, Jiangzhi, Mei, Donghei, Yi, Cheol-Woo, Kim, Do Heui, Peden, Charles, Allard, Jr, Lawrence Frederick, and Szanyi, Janos. Co-ordinatively Unsaturated Al3+ Centers as Binding Sites for Active Catalyst Phases of Platinum on -Al2O3. United States: N. p., 2009.
Web. doi:10.1126/science.1176745.
Kwak, Ja Hun, Hu, Jiangzhi, Mei, Donghei, Yi, Cheol-Woo, Kim, Do Heui, Peden, Charles, Allard, Jr, Lawrence Frederick, & Szanyi, Janos. Co-ordinatively Unsaturated Al3+ Centers as Binding Sites for Active Catalyst Phases of Platinum on -Al2O3. United States. https://doi.org/10.1126/science.1176745
Kwak, Ja Hun, Hu, Jiangzhi, Mei, Donghei, Yi, Cheol-Woo, Kim, Do Heui, Peden, Charles, Allard, Jr, Lawrence Frederick, and Szanyi, Janos. 2009.
"Co-ordinatively Unsaturated Al3+ Centers as Binding Sites for Active Catalyst Phases of Platinum on -Al2O3". United States. https://doi.org/10.1126/science.1176745.
@article{osti_982389,
title = {Co-ordinatively Unsaturated Al3+ Centers as Binding Sites for Active Catalyst Phases of Platinum on -Al2O3},
author = {Kwak, Ja Hun and Hu, Jiangzhi and Mei, Donghei and Yi, Cheol-Woo and Kim, Do Heui and Peden, Charles and Allard, Jr, Lawrence Frederick and Szanyi, Janos},
abstractNote = {In many heterogeneous catalysts, the interaction of metal particles with their oxide support can alter the electronic properties of the metal and can play a critical role in determining particle morphology and maintaining dispersion. We used a combination of ultrahigh magnetic field, solid-state magic-angle spinning nuclear magnetic resonance spectroscopy, and high-angle annular dark-field scanning transmission electron microscopy coupled with density functional theory calculations to reveal the nature of anchoring sites of a catalytically active phase of platinum on the surface of a {gamma}-Al{sub 2}O{sub 3} catalyst support material. The results obtained show that coordinatively unsaturated pentacoordinate Al{sup 3+} (Al{sub penta}{sup 3+}) centers present on the (100) facets of the {gamma}-Al{sub 2}O{sub 3} surface are anchoring Pt. At low loadings, the active catalytic phase is atomically dispersed on the support surface (Pt/Al{sub penta}{sup 3+} = 1), whereas two-dimensional Pt rafts form at higher coverages.},
doi = {10.1126/science.1176745},
url = {https://www.osti.gov/biblio/982389},
journal = {Science},
issn = {0036-8075},
number = 5948,
volume = 325,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 2009},
month = {Thu Jan 01 00:00:00 EST 2009}
}