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At
a power level of 1000
W/m2, the
solar energy incident on
the earth's surface is
theoretically sufficient
to cover all human
energy needs. Using
suitable catalysts, this
solar energy can be used
to convert water into
hydrogen and oxygen -
the fuels of a
hydrogen-based energy
economy.
H2O --> 0.5 O2
(g) + H2 (g)
?G
= +237 kJ/mol
(1. 3 eV/e, ?min = 1100 nm)
The
goal of this project is
to assemble catalysts in
solution phase from
inorganic nanoparticles
with proven efficiencies
for light absorption,
water reduction and
oxidation. Advantages of
this modular approach
are that:
(1) sensitive
semiconductors can be
protected from
photochemical corrosion
by using metal and metal
oxide nanoparticles as
separate sites for
reduction and oxidation
of waterelectrodes to
create devices that can
be integrated into
existing technology.
(2) light absorbance and
redox catalysis can be
independently optimized
by varying nanoparticle
components (sizes and
materials).
(3) electron-hole
separation and charge
transfer can be
optimized with
rectifying Schottky
barriers between the
particles.
Nanoparticles are
essential building
blocks for these
catalyst because their
mass and charge transfer
is fast, and because
they exhibit increased
light absorption and
reduced light
scattering. The final
catalyst particles will
be micrometer sized, and
can be suspended in the
reaction medium (water
or methanol) or they can
be mounted on electrodes
to create devices that
can be integrated into
existing technology.
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Charge Separation in a Niobate Nanosheet Photocatalyst Studied
with Photochemical Labeling,
Erwin M. Sabio, Miaofang Chi, Nigel D. Browning, and Frank E. Osterloh,
Langmuir,
In Press
DOI:
10.1021//la904377f. |
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Evolution of physical and photocatalytic properties in the layered titanates A2Ti4O9 (A=K, H) and in nanosheets derived by chemical exfoliation,
Mark Allen, Arthur Thibert, Erwin M. Sabio, Nigel Browning, Delmar S. Larsen, and Frank E. Osterloh,
Chem. Mater., (Materials Chemistry of Energy Conversion Special Issue)
2010, 22 (3), 1220-1228.
DOI:
10.1021/cm902695r. |
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Unique LaTaO4 Polymorph for Multiple Energy Applications,
May Nyman, Mark A. Rodriguez, Lauren E. S. Rohwer, James E. Martin, Mollie Waller, and Frank E. Osterloh, Chem. Mater.,
2009,
211 (19),
4731-4737.
DOI:
10.1021/cm9020645. |
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Osterloh, F. E.,
Nanoparticle-Assembled Water Splitting Catalysts,
In Solar Hydrogen & Nanotechnology,
Vayssieres, L., Ed, In Press, Wiley VCH.
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Niobate Nanosheets as catalysts for Photochemical Water Splitting into Hydrogen and Hydrogen Peroxide,
Owen C.
Compton and
Frank E.
Osterloh, J.
Phys. Chem. C,
2009,
113 (1),
479-485.
DOI:
10.1021/jp807839b. |
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K4Nb6O17-derived
Photocatalysts
for Hydrogen
Evolution from
Water:
Nanoscrolls
versus
Nanosheets,
Michael C.
Sarahan;
Elizabeth C.
Carroll; Delmar
S. Larsen; Nigel
D. Browning; and
Frank E.
Osterloh, J.
Solid State Chem,
2008,
181 (7),
1681-1686.
DOI:
10.1016/j.jssc.2008.06.021. |
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First
Demonstration of
CdSe as a
Photocatalyst
for Hydrogen
Evolution from
Water under UV
and visible
light, F.
Andrew Frame;
Elizabeth C.
Carroll; Delmar
S. Larsen;
Michael Sarahan;
Nigel D.
Browning; Frank
E. Osterloh,
Chem. Comm.,
2008,
2206-2208.
DOI:
10.1039/b718796c. |
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A Building
Block Approach
towards
Photochemical
Water Splitting
Catalysts based
on Niobate
Nanosheets,
Owen C. Compton;
Cory H. Mullet;
Shirley Chiang;
Frank E.
Osterloh, J.
Phys. Chem. C,
2008,
112(15),
6202-6208.
DOI:
10.1021/jp711589z. |
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»
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Ultrafast
Carrier Dynamics
in Exfoliated
and
Functionalized
Calcium Niobate
Nanosheets in
Water and
Methanol,
Elizabeth C.
Carroll, Owen C.
Compton, Dorte
Madsen, Frank E.
Osterloh, Delmar
S. Larsen, J.
Phys. Chem. C, 2008,
112(7),
2394-2403.
DOI:
10.1021/jp077427d. |
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Inorganic
Materials as
Catalysts for
Photochemical
Splitting of
Water, Frank
E. Osterloh,
Chem. Mater.,
2008,
20(1),
35-54.
DOI:
10.1021/cm7024203. |
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Calcium
Niobate
Semiconductor
Nanosheets at
Catalysts for
Photochemical
Hydrogen
Evolution from
Water, Owen
C. Compton,
Elizabeth C.
Carroll, Jin Y.
Kim, Delmar
Larsen, Frank E.
Osterloh, J.
Phys. Chem. C,
2007,
111(40),
14589-14592.
DOI:
10.1021/jp0751155 |
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Planar
Polarized Light
Emission From
CdSe
Nanoparticle
Clusters,
Jin Young Kim,
Hiroki Hiramatsu,
Frank E.
Osterloh, J.
Am. Chem. Soc.,
2005,
127(44),
15556-15561.
DOI:
10.1021/ja0541377 |
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ZnO-CdSe
Nanoparticle
Clusters as
Directional
Photoemitters
with Tunable
Wavelength,
Jin Young Kim,
Frank E.
Osterloh, J.
Am. Chem. Soc,
2005,
127 (29),
10152-10153.
DOI:
10.1021/ja052735f |
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This project is supported by grant #0829142 from the National Science Foundation. |
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