NanoIntegris is a nanotechnology company based in Boisbriand, Quebec specializing in the production of enriched, single-walled carbon nanotubes. ^[1] In 2012, NanoIntegris was acquired by Raymor Industries, a large-scale producer of single-wall carbon nanotubes using the plasma torch process.

The proprietary technology through which NanoIntegris creates its products spun out of the Hersam Research Group ^[2] at Northwestern University. ^[3]

Process

The process through which these technologies emerged is called Density Gradient Ultracentrifugation (DGU). DGU has been used for some time in biological and medical applications ^[4] but Dr. Mark Hersam utilized this process with carbon nanotubes which allowed for those nanotubes with semi-conductive properties to be separated from those with conductive properties. While the DGU method was the first one to convincingly produce high-purity semiconducting carbon nanotubes, the rotation speeds involved limit the amount of liquid, and thus nanotubes, that can be processed with this technology. NanoIntegris has recently licensed a new process using selective wrapping of semiconducting nanotubes with conjugated polymers. ^[5] This method is scalable thus enabling the supply of this material in large quantities for commercial applications.

Products

Semiconducting SWCNT

Enriched Semiconducting carbon nanotubes (sc-SWCNT) using either a density-gradient ultracentrifugation (DGU) or a polymer-wrapping (conjugated polymer extraction(CPE)) method. While the DGU method is used to disperse and enrich sc-SWCNT in an aqueous solution, the CPE method disperses and enriches sc-SWCNT in non-polar aromatic solvents ^[6]

Conducting SWCNT

Enriched Conducting carbon nanotubes ^[7]

PlasmaTubes SWCNT

Highly graphitized single-wall carbon nanotubes grown using an industrial-scale plasma torch. Nanotubes are grown using a plasma torch display diameters, lengths, and purity levels comparable to the arc and laser methods. The nanotubes measure between 1 and 1.5 nm in diameter and between 0.3-5 microns in length. ^[8]

Pure and SuperPureTubes SWCNT

Highly purified carbon nanotubes. Carbon impurities and metal catalysts impurities below 3% and 1.5% respectively. ^[9]

PureSheets/Graphene

1-4+ layer graphene sheets obtained by liquid exfoliation of graphite ^[10]

HiPco SWCNT

Small-diameter single-walled carbon nanotubes ^[11]

Applications

Field-Effect Transistors

Both Wang ^[12] and Engel ^[13] have found that NanoIntegris separated nanotubes "hold great potential for thin-film transistors and display applications" compared to standard carbon nanotubes. More recently, nanotube-based thin film transistors have been printed using inkjet or gravure methods on a variety of flexible substrates including polyimide ^[14] and polyethylene (PET) ^[15] and transparent substrates such as glass. ^[16] These p-type thin film transistors reliably exhibit high-mobilities (> 10 cm^2/V/s) and ON/OFF ratios (> 10^3) and threshold voltages below 5 V. Nanotube-enabled thin-film transistors thus offer high mobility and current density, low power consumption as well as environmental stability and especially mechanical flexibility. Hysterisis in the current-voltage curves as well as variability in the threshold voltage are issues that remain to be solved on the way to nanotube-enabled OTFT backplanes for flexible displays.

Transparent Conductors

Additionally, the ability to distinguish semiconducting from conducting nanotubes was found to have an effect on conductive films. ^[17]

Organic Light-Emitting Diodes

Organic Light-Emitting Diodes (OLEDs) can be made on a larger scale and at a lower cost using separated carbon nanotubes. ^[12]

High Frequency Devices

By using high-purity, semiconducting nanotubes, scientists have been able to achieve "record...operating frequencies above 80 GHz." ^[18]

References