Coordinatively unsaturated Al3+ centers as binding sites for active catalyst phases on γ-Al2O3

Journal Article · Thu Sep 24 04:00:00 EDT 2009 · Science, 325(5948):1670-1673

DOI:https://doi.org/10.1126/science.1176745· OSTI ID:965555

Kwak, Ja Hun; Hu, Jian Z; Mei, Donghai; Yi, Cheol-Woo W; Kim, Do Heui; Peden, Charles HF; Allard, Larry; Szanyi, Janos

A combination of ultrahigh resolution spectroscopy and microscopy techniques (ultrahigh magnetic field solid state magic angle spinning nuclear magnetic resonance (MAS-NMR) and high-resolution scanning transmission electron microscopy (HR-STEM)) coupled with first principles DFT calculations reveal the nature of anchoring sites of a catalytically active phase onto the surface of γ-Al2O3. The results obtained unambiguously prove that coordinatively unsaturated penta-coordinate Al3+ (Al3+penta) centers present on the (100) facets of the γ-Al2O3 surface are the sites where the anchoring of Pt occurs. At low loadings, the active catalytic phase is atomically dispersed on the support surface (Pt/ Al3+penta=1), while two dimensional Pt rafts form at higher coverages.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 965555
• Report Number(s): PNNL-SA-67165; 9103a; 19799; KC0302010
• Journal Information: Science, 325(5948):1670-1673, Journal Name: Science, 325(5948):1670-1673 Journal Issue: 5948 Vol. 325; ISSN 0193-4511; ISSN SCEHDK
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ALUMINIUM OXIDES
BINDING ENERGY
CATALYST SUPPORTS
CATALYSTS
DENSITY FUNCTIONAL METHOD
Environmental Molecular Sciences Laboratory
NUCLEAR MAGNETIC RESONANCE
PLATINUM
SCANNING ELECTRON MICROSCOPY
SURFACE PROPERTIES
TRANSMISSION ELECTRON MICROSCOPY