Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


UC Riverside scientists discovering new uses for tiny carbon nanotubes

Adding ionic liquid to nanotube films could build smaller gadgets, and create more cost effective 'Smart Windows' that darken in bright sun

The atom-sized world of carbon nanotubes holds great promise for a future demanding smaller and faster electronic components. Nanotubes are stronger than steel and smaller than any element of silicon-based electronics—the ubiquitous component of today's electrical devices—and have better conductivity, which means they can potentially process information faster while using less energy.

The challenge has been figuring out how to incorporate all those great properties into useful electronic devices. A new discovery by four scientists at the University of California, Riverside has brought us closer to the goal. They discovered that by adding ionic liquid—a kind of liquid salt—they can modify the optical transparency of single-walled carbon nanotube films in a controlled pattern.

"It was a discovery, not something we were looking for," said Robert Haddon, director of UC Riverside's Center for Nanoscale Science and Engineering. Scientists Feihu Wang, Mikhail Itkis and Elena Bekyarova were looking at ways to improve the electrical behavior of carbon nanotubes, and as part of their research they also looked at whether they could modulate the transparency of the films. An article about their findings was published online in April in Nature Photonics.

The scientists spent some time trying to affect the optical properties of carbon nanotube films with an electric field, with little success, said Itkis, a research scientist at the Center for Nanoscale Science and Engineering. "But when we applied a thin layer of an ionic liquid on top of the nanotube film we noticed that the change of transparency is amplified 100 times and that the change in transparency occurs in the vicinity of one of the electrodes, so we started studying what causes these drastic changes and how to create transparency in controlled patterns."

An ionic liquid contains negative and positive ions which can interact with the nanotubes, dramatically influencing their ability to store an electrical charge. That increases or decreases their transparency, similar to the way that glasses darken in sunlight. By learning how to manipulate the transparency, scientists may be able to start incorporating nanotube films into products that now rely on slower or heavier components, such as metal oxide.

For instance, using nanotube films meshed with a film of ionic liquid, scientists could create more cost effective Smart Windows, that darken when it's hot outside and become lighter when it's cold.

"Smart Windows are a new industry that has been shown to save 50 percent of your energy costs," said Itkis. "On a very hot day you can shade your window just by turning a switch, so you don't have to use as much air conditioning. And on a winter day, you can make a window more transparent to let in more light."

The scientists still need to study the economic viability of using nanotube film, but Bekyarova said one possible advantage would be that carbon nanotubes are ultra thin—about 1,000 times smaller than a single strand of hair—so you would need very little to cover a large area, such as the windows of a large building.

Itkis said nanotube films also hold great promise in building lighter and more compact analytical instruments such as spectrometers, which are used to analyze the properties of light.

In this application, a nanotube film with an array of electrodes can be used as an electrically configurable diffraction grating for an infrared spectrometer, allowing the wavelength of light to be scanned without moving parts.

Furthermore, by using addressable electrodes, the spatial pattern of the induced transparency in the nanotube film can be modified in a controlled way and used as an electrically configurable optical media for storage and transfer of information via patterns of light.

Carbon nanotubes have great potential, but there is still plenty of work to be done to make them useful in electronics and optoelectronics, Haddon said.

"The challenge is to harness their outstanding properties," he said. "They won't be available at Home Depot next week, but there is continuing progress in the field."

The University of California, Riverside ( is a doctoral research university, a living laboratory for groundbreaking exploration of issues critical to Inland Southern California, the state and communities around the world. Reflecting California's diverse culture, UCR's enrollment has exceeded 21,000 students. The campus will open a medical school in 2013 and has reached the heart of the Coachella Valley by way of the UCR Palm Desert Center. The campus has an annual statewide economic impact of more than $1 billion. A broadcast studio with fiber cable to the AT&T Hollywood hub is available for live or taped interviews. UCR also has ISDN for radio interviews. To learn more, call (951) UCR-NEWS.

By Jeanette Marantos

Iqbal Pittalwala | EurekAlert!
Further information:

More articles from Materials Sciences:

nachricht From ancient fossils to future cars
21.10.2016 | University of California - Riverside

nachricht Study explains strength gap between graphene, carbon fiber
20.10.2016 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>