Molecular Simulations of

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Molecular Simulations of Nano- and Bio-Materials
Venkat Ganesan
Venkat Ganesan CPE 3.414, 471-4856.
venkat_at_che.utexas.edu
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Research Group and Projects
Theme Computer simulations and models to address
how the synthetic chemistry controls the
self-assembly and properties of polymeric,
colloidal and biological materials
Graduate Students Projects M. Shah
Photovoltaics and Solar Cells. Landry K
Properties of Polymer Nanocomposites. David
Trombly Protein-Polysaccharide Mixtures. C.
Mahajan Properties of Fuel Cell
Membranes. Thomas Lewis Dendrimer-DNA
complexes.
Postdocs Dr. Victor Pryamitsyn Simulations of
properties of polymer nanocomposites.
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Recent Graduates

• Brian Besancon Air Liquide.
• Bharad Narayanan Frito Lay, Pepsico.
• Megha Surve Shell RD for Computational
  Research.
• Jamie Kropka Sandia National Laboratories.
• Brad Olsen co-advisor (Primary advisor Rachel
  
• Segalman, UC Berkeley) Assistant Professor,
  MIT.
• Bill Krekelberg (w/Prof. Truskett) Postdoc at
  UT Austin

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Materials Science The New Challenges
Molecular Characteristics
Thermodynamic Conditions
Flow Fields (Nonequilibrium)
Advanced Materials
Lack of fundamental understanding of the
properties of the new materials (Back to Mix and
Shake ?)
Required A fundamental understanding leading to
predictive tools and models for the rational
design of new materials.
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Fuel Cell Membranes
Proton conducting polymer membrane
Burning issue in fuel cell design Can we design
polymers and exploit their assembly to enhance
the cell performance ? Missing fundamental
link How does morphology determine the cell
performance ?
Proton transfer through polymer backbone
Performance
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Fuel Cell Membranes
Funded by Office of Naval Research to develop
efficient portable power sources
Prof. Manthiram (ME)
Prof. Bielawski (Chemistry)
Evaluate Cell Performance
Synthesize Polymers
Test and validate
Develop new polymers
Develop predictive models relating polymer
chemistry to cell performance
Prof. Ganesan (ChE)
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Similarities between Fuel Cell, Photovoltaics
and Solar Cells
Design question in polymer solar
cells/photovoltaics Can we design polymers and
exploit their assembly to enhance the device
performance ? Missing fundamental link How does
morphology determine the cell performance ?

• Solar cells require continuous nano-channels for
  transport of electrons and holes between the two
  electrodes
• Recent idea Use a block copolymer

donor
acceptor

• Such polymers self-assemble into morphologies

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What are Polymer Nanocomposites ?
Fullerenes/ Buckyballs
Single- and Multi-Walled Carbon Nanotubes
Montmorillonite Clays
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Electrical Conductivity of Polymer-Nanotube
Composites
A 108 enhancement at a loading of 0.2!
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Issues in Polymer Nanocomposites
Polymer-Polymer
Polymer-Filler
Filler-Filler
Why ?
How ?
Landry
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Outstanding Technical Challenges
Need to understand phenomena over a vast span of
length and time scales !!

A - nm
mm
nm
mm to cm
Properties
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Tools of The Trade
Process Models (Unit Operations)
Statistical Mechanics, Models
Time
Continuum Models (Fields)
Mesoscale Models (Segments, Blobs)
New, novel simulation tools
Molecular Dynamics (Atoms, Bonds)
Montecarlo, Molecular dynamics incorporating
atomistic details
Quantum Mechanics (Electrons)
Fundamental mechanisms of proton conduction
Length
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• Research Philosophy for the Group Provide a
  collaborative environment with strong
  interactions with complementary experimentalists
  and theorists to enable the students to achieve
  the best education and professional goals.
• Experimental Collaborators
• Prof. Chris Bielawski
• Prof. Ram Manthiram
• Prof. Al Bard
• Prof. Donald Paul
• Prof. Benny Freeman
• Prof. Rachel Segalman
• (Berkeley)
• Prof. Chang Ryu (RPI)

Theory Collaborators Prof. Thomas Truskett
Prof. Dima Makarov (Chemistry)