Centrifugal Length Sorting of Carbon Nanotubes Dr. Jeffrey Fagan

Nanotubes (SWCNTs) come as a low purity mixture of many types and lengths. 10 – 30 Different Producers. Current price  $200 - $750 / gram. Single Wall Carbon Nanotubes Nanotubes are rolled up sheets of graphite. How they are rolled up determines their electrical properties. The length can be from < 10 nm to microns or more. Image courtesy of wikipedia.org

Nanotube Market Composites Medical Energy Electronics Market is rapidly growing. Many potential applications. ~ 30 Major Producers Chemical & Engineering News Carbon Nanotubes By The Metric Ton November 12, 2007, Volume 85 (46), pp

Market Problem Composites Medical Energy Electronics ~ 30 Major Producers There is a disconnect between SWCNT quality and application’s needs. X ~ 10 – 50 % Nanotubes

Market Problem Composites Medical Energy Electronics Value addition in the processing. Some application require sorted material. ~ 10 – 50 % Nanotubes > 90 % Nanotubes Purified Separated

We invented a technology to use a centrifuge to sort mixtures of tubes into different lengths. Our technology allows the economical sorting of single wall carbon nanotubes (SWCNTs) by length. Technology works for all SCWNT types. Technology

At bench scale 10 mg / day separation is easy, and at < $4 / mg total cost. Other separations typically cost $20 - $30 / mg or more. Our separation is scalable, current 10 mg /day is > 20 X larger than any competitor technique Technology Different types of long SWCNTs.

Technology Longer SWCNTs have better optical and Better Properties  higher value Sorting  grades for different markets. Raw Soot PurifiedSeparated Applications mechanical properties.

Medical Applications Transparent Conductive Electrodes Other Electronics Super / Ultracapacitor material Flexible Electronics Circuitry RFID tags Other Energy Solar Cells Batteries Fuel Cells Energy Absorbing Material Applications:

Length affects interactions with cells. Applications: Only some SWCNTs are useful. Need to control the cell uptake. Less material  fewer side effects. IMR 90 with > 200 nm SWNTs (cyan) None enter the cell in 16 hours IMR 90 with < 200 nm SWNTs (red) Large numbers enter in < 16 hours IMR 90 Human Lung Cell Stained green for visualization Medical Applications

Market Sizes Target agents: Cancer Drugs Alone  $45 Billion in 2007 Biosensors:  $5.1 Billion in 2006 Ability to sense glucose and other commercially important bio- molecules already demonstrated Cost not an issue for medical applications, only the ability to meet required physical properties. Sorting reduces the amount required. Minimize EHS risks and liabilities Maximize chance of FDA regulatory approval Size selection allows for greatly enhanced properties or property targeting while substantial reducing the required amount of SWCNTs for a given goal. Size selection eliminates impurities that could otherwise limit or cause regulatory approval failure. Medical Sensors / Target Agents / Imaging Probes Medical ApplicationsApplications:

SWCNTs offer a cheap replacement for ITO Current market for ITO is  $1 Billion/year 10 % annual growth forecast for the next 5 -6 years. Sorted SWCNTs are tougher, flexible and more transparent than ITO Separation  Multiple grades  more value extraction. Applications:Conductive Coatings Image courtesy of Apple Short time to market, likely years Images courtesy of Dell

NIST is planning several SWCNT reference materials (RMs) in FY Raw Soot, Purified and Size sorted populations based on this technology will be produced. These materials will allow for significant industrial advances in measurements, as well as traceability to NIST standards. Reference Material to Support Technology in Early 2009

Collaboration Dr. Kalman Migler NIST – Polymers Division 100 Bureau Drive, MS 8542 Gaithersburg, MD Tel: OpportunitiesContact Technical Dr. Jeffrey Fagan NIST: Polymers Division 100 Bureau Drive, Mail Stop 8542 Gaithersburg, MD Tel: