Carbon nanotube 'ink' may lead to thinner, lighter transistors and solar cells

Jan 08, 2009 By Anne Ju
An atomic force microscope image of semiconducting nanotubes, after the cycloaddition process of removing the metallic tubes.

(PhysOrg.com) -- Using a simple chemical process, scientists at Cornell and DuPont have invented a method of preparing carbon nanotubes for suspension in a semiconducting "ink," which can then be printed into such thin, flexible electronics as transistors and photovoltaic materials.

The method, which involves treating carbon nanotubes with fluorine-based molecules, is reported in the Jan. 9 issue of the journal Science (Vol. 323 No. 234). The research was jointly led by Graciela B. Blanchet, a research fellow at DuPont, and George Malliaras, Cornell associate professor of materials science and engineering and the Lester B. Knight Director of the Cornell NanoScale Science and Technology Facility. Helen Lu, a research chemist at Dupont, and Mandakini Kanungo, a former Cornell postdoctoral fellow now at Xerox, also worked on the project.

Carbon nanotubes are good candidates for transistors in low-cost, printable electronics, but only after large quantities of them have been converted into semiconductors. When carbon nanotubes are grown in the lab, some are semiconducting but others are metallic, and they are difficult to separate from each other.

An atomic force microscope image of both metallic and semiconducting carbon nanotubes, before the cycloaddition process of removing the metallic tubes.


This mix is a major drawback in creating transistors from nanotubes, Malliaras said. The Cornell/DuPont team concentrated on a new, inexpensive way to eliminate the metallic tubes, preparing them for such applications as suspension in semiconducting ink for printing.

To do so, the researchers brought fluorine-based molecules into contact with the nanotubes. Through a process called cycloaddition, the fluorine molecules efficiently attacked or converted the metallic nanotubes, leaving the semiconducting tubes alone, and creating a perfect batch of solely semiconducting nanotubes.

"Our work suggests that careful control of the chemical reaction enables the complete conversion of metallic tubes without the degradation of semiconducting tubes," Blanchet said.

The work should lead to exploration of a wide range of devices, such as novel organic photovoltaic structures, Malliaras added.

For the past several years, scientists from Cornell and DuPont have worked together on a variety of projects involving flexible electronics. The research is funded by a grant from the U.S. Air Force for developing transistors from carbon nanotubes.

Provided by Cornell University

Explore further: Engineers discover new method to determine surface properties at the nanoscale

add to favorites email to friend print save as pdf

Related Stories

Revolutionary solar-friendly form of silicon shines

Nov 17, 2014

Silicon is the second most-abundant element in the earth's crust. When purified, it takes on a diamond structure, which is essential to modern electronic devices—carbon is to biology as silicon is to technology. ...

Researchers develop world's thinnest electric generator

Oct 15, 2014

Researchers from Columbia Engineering and the Georgia Institute of Technology report today that they have made the first experimental observation of piezoelectricity and the piezotronic effect in an atomically ...

Doped graphene nanoribbons with potential

Sep 08, 2014

Graphene is a semiconductor when prepared as an ultra-narrow ribbon – although the material is actually a conductive material. Researchers from Empa and the Max Planck Institute for Polymer Research have ...

Phosphorus a promising semiconductor

Sep 08, 2014

(Phys.org) —Defects damage the ideal properties of many two-dimensional materials, like carbon-based graphene. Phosphorus just shrugs.

Move over, silicon? New transistor material tested

Jun 30, 2014

For the ever-shrinking transistor, there may be a new game in town. Cornell researchers have demonstrated promising electronic performance from a semiconducting compound with properties that could prove a ...

Recommended for you

New 2-D quantum materials for nanoelectronics

Nov 21, 2014

Researchers at MIT say they have carried out a theoretical analysis showing that a family of two-dimensional materials exhibits exotic quantum properties that may enable a new type of nanoscale electronics.

Thin film produces new chemistry in 'nanoreactor'

Nov 19, 2014

Physicists of the University of Groningen and the FOM Foundation, led by professor Beatriz Noheda, have discovered a new manganese compound that is produced by tension in the crystal structure of terbium manganese oxide. ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.