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Nanomaterials: Why Size Matters.Current & Potential Impact of Nanotechnology
“Nano is Everywhere”
April 17, 2010INNOVATION
Teaching Nanotechnology within Virginia SOLsCenter for Diversity in Engineering, University of Virginia
Lisa E. Friedersdorf, PhDManaging Director, nanoSTAR Institute, UVa
President, AdviSci
Materials in General
Lets start with bulk materials….What are typical material classifications?What are the basic properties?(mechanical, thermal, electrical, etc.)
Tm - Melting Temperaturephase transformation from solid (tightly bound) to liquid (loosely bound)
E - Stiffnessresistance to elastic deformation (non- permanent)
α - Thermal Expansion Coefficientfractional change in length with one degree change in T
Why?
Let’s compare the following properties for metals, ceramics, and polymers.
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
What’s the BIG deal about something so SMALL?Materials behave differently at this size scale. Unique and interesting properties…
for example Gold, Silver, Allotropes of Carbon
Applications are endless!
Color depends on particle size Core & Core-Shell Quantum Dots, Evident Technologies
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
As the particle size gets smaller, a higher fraction of the atoms are at the surface.
Size Matters
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Electrical properties as an example
Callister, Wiley
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Metals Insulators and semiconductors
Callister, Wiley
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Quantum DotsToo small to consider continuous bands in electronic structure.
Phillips Research
Floro, MSE
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
It’s not just size, arrangement matters, too. For example, allotropes of Carbon
http://www.chem.wisc.edu/~newtrad/CurrRef/BDGTopic/BDGtext/BDGIntro.html
BuckyballsDiamonds
Graphite
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Carbonaceous NanomaterialsBuckyballs (fullerenes) NanotubesNanosheetsNano-onions
Smalley, et alNature 1985
Bethune, Dorn, Stevenson Nature 1994; Stevenson, Balch, Bible, Dorn, et al. Nature 1999
Iijima, et al. Nature 1993, Bethune, et al. Nature 1993
Harry Dorn - VT
Petra Reinke, UVACarbon Onions, clusters
Brian Holloway - CWM
NanoSheets(APL 2004)
MWNT, Albin, ODU
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Carbonaceous nanomaterials are exciting because of their amazing material properties.
Nanotubes, for example:Mechanical
100 times stronger than steelElectrical
Conduct electricity better than copperDepending on “flavor” metal or semiconductor
ThermalConduct heat better than diamonds
Optical/ Surface/ Geometry, etc. properties also being exploited
NASA
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
So now, at the nanoscale, we have to rethink how materials behave.
It is an exciting time for a scientist…
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
NanoelectronicsThen: Gigantic Computers Now: Handheld Devices
The very first computers were highly inefficient and took up incredible amounts of space. This computer,
ENIAC, was built in 1946.
Computers can now fit in your hand. Many handheld devices have more computing power
than the computer to the left.
yorkblog.com cybernetnews.com
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Impact of Nanoscience on Medicine
Chemotherapy, a leading treatment in the past, while effective in killing cancerous cells also kills healthy cells.
Loading gold nanoparticles with cancer killing drugs allows for targeting of malignant cells exclusively.
ACS Publications, Nano LettersPangaea Clinic of Naturopathic Medicine
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
MedicineTEM Image of Uranyl Acetate-Stained Encapsidated
5 nm Gold Nanoparticles in GTA Proheads (80,000X)
singlyfilled
empty
doublyfilled
Spano, Biology
Botchwey, BMEGillies, MAE
Landers, Chemistry
Kelly, BME
Sheng, Radiation Oncology
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010UBC
Alternative Energy
Fuel Cells
Solar Cells
Organic Solar Cells
Laser-textured Silicon for Solar Cells
McIntosh, ChE
McGrath, VT
Gupta, ECE
Heflin, VT
Loth, MAE
RET, University of Virginia Lisa E. Friedersdorf, PhD April 17, 2010
Thank you.
Questions?
