William Marsh Rice University

R Bruce Weisman

Sergei M Bachilo

Richard E Smalley

Ramesh Sivarajan

Robert H Hauge

Michael S Strano

W Carter Kittrell

Satish Nagarajaiah

Paul A Withey

Venkata Srivishnu M Vemuru

Eric Christopher Booth

In some embodiments, the present invention provides methods of detecting strain associated with an object by: (1) irradiating a composition that has been applied to the object, where the composition comprises semiconducting single-walled carbon nanotubes; (2) measuring an emission from the irradiated composition, where the emission comprises near infrared emission; and (3) correlating the near infrared emission to the presence or absence of strain associated with the object. In some embodiments, the aforementioned steps occur without physically contacting the object or the composition. In some embodiments, the aforementioned steps occur without utilizing Raman spectroscopy. Further embodiments of the present invention also include a step of applying the composition to the object.

Non-contact strain sensing of objects by use of single-walled carbon nanotubes

The present invention is directed toward fluorescent inks and markers comprising carbon nanotubes. The present invention is also directed toward methods of making such inks and markers and to methods of using such inks and markers, especially for security applications (e.g., anti-counterfeiting). Such inks and markers rely on the unique fluorescent properties of semiconducting carbon nanotubes.

Fluorescent security ink using carbon nanotubes

The invention relates to a process for sorting and separating a mixture of (n, m) type single-wall carbon nanotubes according to (n, m) type. A mixture of (n, m) type single-wall carbon nanotubes is suspended such that the single-wall carbon nanotubes are individually dispersed. The nanotube suspension can be done in a surfactant-water solution and the surfactant surrounding the nanotubes keeps the nanotube isolated and from aggregating with other nanotubes. The nanotube suspension is acidified to protonate a fraction of the nanotubes. An electric field is applied and the protonated nanotubes migrate in the electric fields at different rates dependent on their (n, m) type. Fractions of nanotubes are collected at different fractionation times. The process of protonation, applying an electric field, and fractionation is repeated at increasingly higher pH to separated the (n, m) nanotube mixture into individual (n, m) nanotube fractions. The separation enables new electronic devices requiring selected (n, m) nanotube types.

Method for separating single-wall carbon nanotubes and compositions thereof

Growing community of inventors

Houston, TX, United States of America

R Bruce Weisman