Molecules Moving Mountains: Materials Science Today and Tomorrow

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Molecules Moving Mountains Materials Science
Today and Tomorrow
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Materials Science Broad Impact
Defense
Electronics
Communication
Space Exploration
Photo courtesy of Corning
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The Small Revolution NanoTechnology
1 nanometer 1 billionth of a meter
When dimensions approach nanometer size, surface
properties dominate resulting in significantly
different material behavior.

• Carbon Nanotubes
• 1000x stronger than steel
• -Metallic or Semiconducting
• High temperature stability
• Chemical Stability

First observed by Iijima, Nature, 1991
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The Potential Impact of NanoTechnology is Broad
Medicine
Electronics
IBM, App. Phys. Let., Vol 73, p. 2447, 1998
Kopelman and Philbert et al., Univ. of Michigan,
2002 Photo by Eric Monson
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So why is a companylike Cat that makes large
earthmoving equipment and electric power
interested in nanoscale technology?
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Steel Development at the Nanoscale
Careful composition and process control to
achieve nanoscale features such as these Titanium
carbonitride particles enhances performance by as
much as 50.
Photo courtesy of Dr. Gautum Ghosh, Northwestern
Univ.
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Emissions Reduction
Engineered at the macro
50 nm
Structured porosity for control of chemical
reactions with active surfaces as high as 1000
m2/g
Reaction vessels from micelles containing only
hundreds of molecules.
20 nm
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Sensors
Emissions Reduction Stringent standards require
sensors to find a needle in a haystack (15-20
parts per million). Extremely selective and
sensitive sensors are required for these
applications.
Analyte Molecules

• Smart Materials
• Embedded sensors that monitor the health of
  structures.
• Robotics or medical implants with artificial
  muscles that respond in a controlled manner.
• Implants in a patients muscle to monitor local
  nerve activity.

II-VI Semiconductor Surface
Photoluminescence (PL) of II-VI semiconductors
can be modulated by adsorption of molecules from
gas and liquid phases.
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Fuel Cells
A fuel cell converts the chemical energy of fuel
directly to power through a controlled chemical
reaction.
Layered structures with nanoscale dimensions
promise to increase ionic conductivity 10 to 1000
times over bulk materials.
Artificial Structures by Pulsed Laser
Ablation (LaMnO3)15.5(SrMnO3)5.5
P. A. Salvador, A.-M. Haghiri-Gosnet, B. Mercey,
M. Hervieu and B. Raveau, Applied Physics
Letters, 75, 2638-2640 (1999).
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Engineered Coatings
Hard, wear resistant engineered coatings on
gears, bearings, and pumps promise to reduce
wear, minimize friction and ultimately extend the
life of components.
Nanometer scale layers such as the WC and C
layers shown here dictate the wear and lubricious
behavior of the coated component.
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Nanomaterials Moving Mountains (of dirt)
Abrasion Resistant Layer