Molecular Routes to Nanoparticulate Alumina

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Molecular Routes to Nanoparticulate Alumina
Dr. Yuzhong Wang, Former Graduate Student,
UK Now Postdoctoral U. Georgia (Robinson) Dr.
Melanie Harvey, Postdoctoral Associate, UK Now
Assistant Prof., St. Marys College, KS Dr.
Sonali Bhandari, Current Postdoctoral,
UK Collaborators Prof. L. Bachas, J. Li,
UK Praxair Surface Technologies, Inc.
(1993-1998) Office of Naval Research (1996 -
2002) Air Force Office of Scientific Research
(pending)
I. Mitsubishi to Materials II. Biological
Composites. III. Core Stability? IV. Other Metal
Oxides
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Bayer Process
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Molecular Routes to Aluminum Oxides
gt 800 C
AlR3 water vapor or oxygen (R alkoxide,
carboxylate, acac, etc.)
?-Al2O3 thin films
Representative Literature Pulver et al. Surf.
Coat. Technol. 125 (2000) 400 Battiston, et al.
Chem. Vap. Dep. 7 (2001) 69
RT
Fireball and AlOOH
AlMe3 water vapor
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Open Trialkylaluminum Bottles in a Moisture-Rich
Drybox Atmosphere
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Praxairs Interest Single Source Precursors to
Corrosion Resistant Coatings of Alumina
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Precursors with AlO 23
?
2 AlR3 2 Al(OEt)3
Al(?-OEt)2AlMe23
toluene
(R Me, Et)
D. A. Atwood, Organometallic Single Source
Precursors for Inorganic Films, Coatings,
and Powders U.S. Pat. Number 6,124,427 (Filed
Mar. 1997, Published Sept. 2000). Atwood,
Jegier, Liu, Rutherford, Wei, Tucker, et al.
Organometallics 1999, 18, 976
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Mitsubishi to Materials
Ambient
Al2O3
Hexane
Amorphous, XRD Pure, EDX Size 18(8) nm C,H lt
0.5 IR, 500 - 1000cm-1(br) surface water,
2900-3700cm-1 27Al NMR, 11, 41, 76 ppm
D.A. Atwood, et al. Chemistry of Materials.
submitted
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An Anomalous TEM ?-Al2O3
(x 400,000)
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Typical TEM of Amorphous Alumina
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Other Molecular Routes to Alumina
Kung, et al. A Soft-Chemical Method to
Synthesize Lewis Acid Surfaces of Aluminum
Oxide Angew. Chem. Int. Ed. Engl. 42 (2003) 2415.
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Gallium-Containing Mitsubishi
?
Al(?-OEt)2GaMe23
3 GaMe3 2 Al(OEt)3
toluene
D.A. Atwood, et al. Organometallics 1999, 18, 976.
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Pepsin
Higher Enzymatic Activity AND Higher Thermal
Stability
Li, Wang, Gavalas, Atwood, Bachas,
Alumina-Pepsin Hybrid Nanoparticles
with Orientation-Specific Enzyme Coupling Nano
Letters 3 (2003) 55
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Multidisciplinary Molecules to Materials
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Core Integrity in Mitsubishi Siloxide
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Sequential Hydrolysis
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MitsubishiChlorides forFurther Derivatization
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Simplified Mixed-Metal Synthesis
(Clusters with Natural Bonding Expected)
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Partial Structure of FexAlyOz Cluster
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Yb(OPri)3 3 AlMe3
?
Yb2(?-OPri)3(?-OH)4Al2Me42(?4-O)
toluene
25 C
amorphous (XRD)
air hexanes
800 C
24 hrs
crystalline Yb3Al5O12
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Y(OPri)3 3 AlMe3
?
Y3(?4-O)(?3-O)2(?-OPri)9Al5Me8(?-Me)2
toluene
25 C
amorphous (XRD)
air hexanes
1100 C
30 min
crystalline Y3Al5O12
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Precursors of Metal Aluminium Oxide Materials