Nanotechnology and Energy: Armchair Quantum Wires
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Transcript of Nanotechnology and Energy: Armchair Quantum Wires
Nanotechnology and Energy:Armchair Quantum Wires
Wade Adams, Howard Schmidt, Bob Hauge, Amy Jaffe, and Rick Smalley* www.nano.rice.edu www.rice.edu/energy
*deceased
The Power
Conference ‘06
UH - GEMI
June 29 , 2006
Professor Richard E. Smalley1943 - 2005
Nobel Prize in Chemistry 1996
A 6 week summer project in 1985
2 – page paper in Nature
C60
Buckminster-
fullerene:
Buckyballswith Robert F. Curl and Harold Kroto
National Nanotechnology ProgramWhite House – November 2003
Humanity’s Top Ten Problemsfor next 50 years
1. ENERGY
2. WATER
3. FOOD
4. ENVIRONMENT
5. POVERTY
6. TERRORISM & WAR
7. DISEASE
8. EDUCATION
9. DEMOCRACY
10. POPULATION2003 6.5 Billion People2050 8-10 Billion People
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The ENERGY REVOLUTION (The Terawatt Challenge)
14 Terawatts
210 M BOE/day 30 -- 60 Terawatts450 – 900 MBOE/day
Energy: The Basis of Prosperity 20st Century = OIL 21st Century = ??
Energy-efficient Commuting
PRIMARY ENERGY SOURCESAlternatives to Oil
TOO LITTLE• Conservation / Efficiency -- not enough• Hydroelectric -- not enough• Biomass -- not enough• Wind -- not enough • Wave & Tide -- not enough CHEMICAL• Natural Gas -- sequestration?, cost?• Gas Hydrates -- sequestration?, cost?• Clean Coal -- sequestration?, cost?
NUCLEAR• Nuclear Fission -- radioactive waste?, terrorism?, cost?• Nuclear Fusion -- too difficult?, cost?• Geothermal HDR -- cost ? , enough?• Solar terrestrial -- cost ?• Solar power satellites -- cost ?• Lunar Solar Power -- cost ?
165,000 TWof sunlighthit the earthevery day
PV Land Area Requirements
20 TW
3 TW
Nathan S. Lewis, California Institute of Technology
Nathan S. Lewis, California Institute of Technology
Solar Cell Land Area Requirements
6 Boxes at 3.3 TW Each = 20 TWe
Nathan S. Lewis, California Institute of Technology
Nathan S. Lewis, California Institute of Technology
≥ 20 TWe from the Moon
David Criswell
Univ. Houston
David Criswell
Univ. Houston
“Harvested
Moon”
Renewable Resource MapsRenewable sources generally remote from major population centers
Source: NREL
US Power Production Map
Source: DOE & Nate Lewis, Caltech
Currently, power is generated close to population centers
One World Energy Scheme for 30-60TW in 2050:The Distributed Store-Gen Grid
• Energy transported as electrical energy over wire, rather than by transport of mass (coal, oil, gas)
• Vast electrical power grid on continental scale interconnecting ~ 100 million asynchronous “local” storage and generation sites, entire system continually innovated by free enterprise
• “Local” = house, block, community, business, town, …• Local storage = batteries, flywheels, hydrogen, etc.• Local generation = reverse of local storage + local solar and geo• Local “buy low, sell high” to electrical power grid• Local optimization of days of storage capacity, quality of local power• Electrical grid does not need to be very reliable, but it will be
robust• Mass Primary Power input to grid via HV DC transmission lines from
existing plants plus remote (up to 2000 mile) sources on TW scale, including vast solar farms in deserts, wind, NIMBY nuclear, clean coal, stranded gas, wave, hydro, space-based solar…”EVERYBODY PLAYS”
• Hydrogen, methanol, ethanol are transportation fuels • Transition technology – Plug-in Hybrids
Energy Nanotech Grand Challengesfrom Meeting at Rice University May 2003
Report available!
1. Photovoltaics -- drop cost by 100 fold.
2. Photocatalytic reduction of CO2 to methanol.
3. Direct photoconversion of light + water to produce H2.
4. Fuel cells -- drop the cost by 10-100x + low temp start.
5. Batteries and supercapacitors -- improve by 10-100x for automotive and distributed generation applications.
6. H2 storage -- light weight materials for pressure tanks and LH2 vessels, and/or a new light weight, easily reversible hydrogen chemisorption system
7. Power cables (superconductors, or quantum conductors) with which to rewire the electrical transmission grid, and enable continental, and even worldwide electrical energy transport; and also to replace aluminum and copper wires essentially everywhere -- particularly in the windings of electric motors and generators (especially good if we can eliminate eddy current losses).
CarbonNanotechnologyLaboratory Making Buckytubes“Be All They Can Be”
Founded by Rick Smalley in 2003 as a division of CNSTCoordinates SWNT Research with 10 Faculty in 6 Departments
Prof. James M. Tour – DirectorProf. Matteo Pasquali – Co-DirectorDr. Howard K. Schmidt - Executive DirectorDr. Robert H. Hauge - Technology Director
If it ain’t tubes, we don’t do it!
MOLECULAR PERFECTION & EXTREME PERFORMANCEMOLECULAR PERFECTION & EXTREME PERFORMANCE
The Strongest Fiber Possible.Selectable Electrical Properties
Metallic Tubes Better Than CopperSemiconductors Better Than InSb or GaAs
Thermal Conductivity of Diamond.The Unique Chemistry of Carbon.The Scale and Perfection of DNA.The Ultimately Versatile Engineering Material.
Why Single Wall Carbon Nanotubes?
Graphene SheetTexas Chicken Wire
SWNT: ROLLED-UP SHEET OF GRAPHITE
World’s largest SWNT model
22 April 2005, Guinness World Record
Model of a 5-5 SWNT
~65,000 pieces
360 m long, 0.36 m wide
about 100 builders
over 1000 in attendance
“Supremely Silly” (from Rick Smalley)
RAJAT DUGGAL(inside giant SWNT model)
Building a 1000-ft SWNT:
Cost of the parts: $6,000
pRICEless
armchair ( = 30°)
zigzag ( = 0°)
intermediate (0 30°)
– Cylindrical graphene sheet– Diameters of 0.7 – 3.0 nm
• Observed tubes typically < 2 nm
– Both metallic and semi-conductor species possible
– Length to diameter ratio as large as 104 – 105
• can be considered 1-D nanostructures
Types of SWNT
Conductivity of Metallic SWNT
• Measurements on individual metallic SWNT on Si wafers with patterned metal contacts
• Single tubes can pass 20 uA for hours
• Equivalent to roughly a billion amps per square centimeter!
• Conductivity measured twice that of copper
• Ballistic conduction at low fields with mean free path of 1.4 microns
• Similar results reported by many
• Despite chemical contaminants and asymmetric environment
Dekker, Smalley, Nature, 386, 474-477 (1997). McEuen, et al, Phys.Rev.Lett.84, 6082
Quantum Tunneling
Alper Buldum and Jian Ping Lu, Phys. Rev. B 63, 161403 R (2001).
Tunneling Evidence• Indirect indication of conductivity
by measuring lifetimes of photo-excited electrons
• Cooling mechanism is interaction with phonons – just like electrical resistivity
• Anomalously long life-times yield mean free path of 15 microns (10x single tubes)
• Based on bundles in ‘buckypapers’ – good local symmetry and clean, but still based on mixture of metals and semi-conductors
• Results imply 10 – 25x better conductivity than copper
Source: Tobias Hertl, et al, Phys. Rev. Lett. 84(21) (2000) 5002
SWNT Quantum WireExpected Features• 1-10x Copper Conductivity• 6x Less Mass• Stronger Than Steel• Zero Thermal Expansion
Key Grid Benefits• Reduced Power Loss• Low-to-No Sag • Reduced Mass• Higher Power Density
SWNT Technology Benefits• Type & Class Specific• Higher Purity• Lower Cost• Polymer Dispersible
CNL Armchair Quantum Wire Program
(armchair swnt wire with electrical conductivity > copper)( 5 years, $25 million )
• SWNT Sorting (the “signal” for the amplifier)
• SWNT Amplifier
• SWNT Purification
• SWNT Fiber Spinning & Processing
• SWNT Continuous Growth
Getting The Right Tube• Often Need A Single Type of SWNT • Current Growth Inadequate
– Mixtures ~ 50 Types– Mixed Metals, Semi-Metals &
Semiconductors– Impure & Inefficient
• N,M Control Critical – Quantum Wire– Electronics & Sensors– Biomedical Therapeutics– Energy Conversion Storage
• Seeded Growth Required– Separates Nucleation From Growth– Eliminate By-Products & Purification– Vastly Improved Efficiency– Sort Once at Small Scale
Rolling Graphite - n,m Vectors
Roll-up vector
SWNT Excitation FluorescenceEach peak comes from a specific semi-conducting SWNT n,m value
SWNT Seeded Growth1. Attach Catalyst 2. Deposit on Inert Surface
3. “Dock” Catalyst4. SWNT Growth
Current Results
Key Starting Materials• Have FeMoC Catalyst• Have Short SWNT Seeds• Have Soluble SWNT
Key Process Steps• In-Solution Attachment• Controlled Deposition• Catalyst Docking• Reductive Etching• Growth is Next !!
SWNTcat Growth
46 nm long
1.8 nm
0.6 nm
120 nm long
1.0 nm
0.6 nm
0.6 nm
Initial 100 mtorr CH4 – 10 min – 800 oC
SWNT AmplifierProcess Flow
Cut
Grow
Disperse
Attach
Dock
SWNTamp Production Concept
SW
NT
+ F
eMoC
Cat
alys
t
Hydro-carbon feedstocks
Seeded Growth500 < T < 700 C
Seed Preparation. (1 lb/ day) Cut SWNT, Prep. Catalyst, Functionalize, Attach, Dock
Mono-Type SWNT(1000 lb / day )
“Inner Loop” Processing
BulkOutput
SWNT Growth RatesSWNT Sample Growth Rate
(m/min)
SWNTcat on HOPG 0.005
SWNT Fiber Continued Growth
0.3
Maruyama Carpet Growth 1
Hata Carpet Growth 250
Free SWNT Growth 600
DNA Replication (Bacteria) 0.340
Science 306, 1362 (2004). Nano Lett. 4, 1025 (2004).
Production Scale-Up Path• Rice made 1 mg / day in 1997
• Lab-scale reactor at 1 gm / hour (2002)
• CNI Pilot plant producing 20 lb /day
• CNI now testing 100 lb / day reactor
Forming SWNT Wires
• Need macro-crystalline SWNT fiber/wire• Starting material is tangled at several scales• Starting material has variety of diameters and
types• Enormous Van der Waals forces make it hard
to separate SWNT bundles
• SWNT bundles swell in superacids• Dispersion due to “protonation” & intercalation of SWNTs
V. A. Davis et. Al., Macromolecues 37, 154 (2004)
Dispersion in Super-Acids
W.-F Hwang and Y. Wang
dried SWNT fiber
in 102% H2SO4
“Spaghetti”In Oleum
• Producing Neat SWNT Fibers• Dry-Spun from Oleum • 6 to 14 Wt. % SWNT Dope• Extruded as 50 µm Dia. Fibers• 109 Tubes in Cross Section • 100 Meters Long
Prototype Wire - SWNT Fibers
Science 305, 1447-1450, 3 September 2004!!!
Ultimate Properties of Polymers
Hermann Staudinger, Die Hochmolekularen Organischen Verbindungen, Berlin: Springer p.111 (1932)
Perfect orientation
Perfect lateral order
Few chain end defects (HMW)
+
INTRINSIC CHAIN PROPERTIES
Staudinger Continuous Crystal Model
SWNT Tensile Strength
Yakobson, et al., Comp. Mat. Sci. 8, 341 (1997).
Predicted tensile strength of single-wall nanotubes >100 GPa
Calculated strain-to-failure >30%
Measurements on small bundles found strength ~30-60 GPa
Quantum Wire on The GridKey Grid Benefits • Eliminate Thermal Failures• Reduce Wasted Power• Reduce Urban R.O.W. Costs• Enable Remote Generation
Grid Applications & Benefits• Eliminate Thermal-Sag Failure: Now a $100B+ a year problem.
• Short-Distance AC: AQW could increase throughput up to ten-fold without increasing losses while using only existing towers and rights-of-way. Avoid new construction in congested urban areas – estimated over $100M per mile.
• Medium-Distance AC: AQW could decrease resistive losses and voltage drop ten-fold if amperage were not increased. This would improve grid dynamics significantly in the range between 100 and 300 miles, where voltage stability limits deliverable power.
• Long-Distance HVDC: AQW could permit amperage throughput ten fold or reduce losses ten-fold. New conventional lines cost $1M to $2M per mile, plus about $250M per AC/DC converter station.
• Remote Power: Could enable utilization of large-scale renewables and remote nuclear.
High Pressure CO (HiPCO) Process
CO + CO 900-1200 C 10-40 atm
Fe, Ni CatalystsCO2 + SWNT + impurities
Rice Univ. Carbon Nanotechnologies, Inc.& NASA
NASASuccess Stories
Continuous process10-100’s g/day Small diameters (0.7nm) Company spin-off (CNI)
Tuesday, April 26Tuesday, April 26thth , ,
2005 -- NASA 2005 -- NASA
Announces new $16M Announces new $16M
Grant to Rice Grant to Rice
University and two University and two
NASA Centers –NASA Centers –
Research to develop Research to develop
the Quantum Wirethe Quantum Wire
CNL Actively
CNL Actively building new
building new collaborations
collaborations to fund this
to fund this critical critical research
research program!!!
program!!!
Energy Energy Fuel cellsFuel cells Supercapacitors and batteriesSupercapacitors and batteries Photovoltaic cellsPhotovoltaic cells ““Quantum Wires”Quantum Wires”
Electronics Electronics Field emissionField emission
– Flat panel displaysFlat panel displays– Back light unitsBack light units– Electron device cathodesElectron device cathodes
SensorsSensors Printable electronicsPrintable electronics Logic and memory devicesLogic and memory devices Interconnects Interconnects
CompositesComposites Electrically conductive composites Electrically conductive composites
– Wide range of conductivitiesWide range of conductivities• AntistaticAntistatic• Electrostatic dissipation Electrostatic dissipation • EMI/RFI shielding EMI/RFI shielding
– Bulk partsBulk parts– Transparent conductive coatingsTransparent conductive coatings– Anti-corrosion coatingsAnti-corrosion coatings
Reinforced compositesReinforced compositesTougher, stronger, stiffer, wear resistant Tougher, stronger, stiffer, wear resistant – Thermosets and thermoplasticsThermosets and thermoplastics
• Parts, coatings Parts, coatings – High performance fibersHigh performance fibers– High performance ceramicsHigh performance ceramics
Thermally conductive composites Thermally conductive composites – Electronics packagingElectronics packaging– Industrial applicationsIndustrial applications
Buckytubes Offer Incredible Opportunities
Roadblocks
• Vision without funding is hallucination.• Da Hsuan Feng – UT Dallas
• Vision without hardware is delusion.• Lockheed engineer
From the age of Space to the age of Medicine
New Energy Research Program(Smalley’s Nickel & Dime Solution)
• For FY06-FY10 collect 5 cents from every gallon of oil product Invest the resultant > $10 Billion per year as additional funding in
frontier energy research distributed among DOE, NSF, NIST, NASA, and DoD.
• For the next 10 years collect 10 cents from every gallon; invest the >$20 Billion per year in frontier energy research.
• Devote a third of this money to New Energy Research Centers located adjacent to major US Research Universities, especially Zip
Code 77005.
• At worst this endeavor will create a cornucopia of new technologies and new industries.
• At best, we will solve the energy problem before 2020, and thereby lay the basis for energy prosperity & peace worldwide.
Leadership• President Bush – State of the Union
Address – Jan 31, 2006– “America is addicted to oil”– Replace oil imports from Middle East by
75% by 2025
• DOE Advanced Energy Initiative 22% increase in clean energy research– Zero emission coal– Solar and wind– Clean, safe nuclear– Batteries, Hydrogen, ethanol
• A BIG change from the 2001 Cheney Energy Report – drill our way to independence!
But…
• Are these ideas tough or aggressive enough?• NO!
– Biofuels budget actually smaller than in FY06– No market signal for more efficient vehicles
• Fuel economy standards – regulatory– 40 mpg in 10 years saves 2.5M BOE/day
• Substantial gas tax – market mechanism
• Up to Congress to execute programs– Incentives for alternate fuel production/vehicles– Funding for research initiatives
The biggest single challenge for the next few decades:
ENERGY for 1010 people
• At MINIMUM we need 10 Terawatts (150 M BOE/day) from some new clean energy source by 2050
• For worldwide energy prosperity and peace we need it to be cheap.
• We simply can not do this with current technology.
• We need Boys and Girls to enter Physical Science and Engineering as they did after Sputnik.
• Inspire in them a sense of MISSION( BE A SCIENTIST --- SAVE THE WORLD )
• We need a bold new APOLLO PROGRAM to find the NEW ENERGY TECHNOLOGY
By 2012, if current trends continue, over 90% of all physical scientists and engineers in the worldwill be Asians working in Asia.
PhD Degrees in Science and Engineering
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US citizens,Physical Sciences and Engineering only
Source: Science and Engineering Indicators, National Science Board, 2002
Education
• American Competitiveness Initiative– Double physical sciences research funding in ten
years (including nanotech, supercomputing, alternative energy sources)
– Permanent R&D Tax Credit– HS Math/Science teacher training (70,000) and add
30,000 M&S professional teachers
• YEA!– But will Congress fund the initiatives?– And will they sustain the funding??
2999
What Can YOU Do Now?
• Learn as much as possible about energy
• Learn as much as possible about nanotechnology
• Encourage kids to study science and engineering!!
Reading Assignments• Twilight in the Desert, Matthew R. Simmons• Winning the Oil Endgame, Amory Lovins• Beyond Oil: The View from Hubbert’s Peak, Kenneth S. Deffeyes• Out of Gas, Daniel Goodstein• The End of Oil, Paul Roberts• The Prize, Daniel Yergin• Hubbert’s Peak, Kenneth S. Deffeyes• The Hydrogen Economy, Jeremy Rifkin• Twenty Hydrogen Myths, Amory Lovins (www.rmi.org) • Matt Simmons, web site: (www.simmons-intl.com) • M.I. Hoffert et. al., Science, 2002, 298, 981, • DOE BES Workshop Report on Hydrogen (www.sc.doe.org/bes/hydrogen.pdf) • 2003 State of the Future, (www.stateofthefuture.org)• Nanotechnology and Energy, 2003 Report, (www.cnst.rice.edu)• National Nanotechnology Program, (www.nano.gov)