Featured Research

from universities, journals, and other organizations

New revolutionary sensor links pressure to color change

Date:
April 30, 2014
Source:
University of California - Riverside
Summary:
A high-resolution pressure sensor indicates pressure by varying its color -- a sensor that all of us can use with just our eyes. This sensor differs from commercially available pressure sensor films. The new technology produces a mosaic of easy-to-distinguish colors and has the benefit of higher contrast and resolution. It can potentially be used in many safety devices for revealing pressure distribution over even very complex surfaces.

Digital images (top) and schematic illustration (bottom) showing the color change of the sensor film after experiencing different amounts of pressure.
Credit: Yin Lab, UC Riverside.

Imagine an automobile crash test that uses test dummies painted all over with a substance that can change color according to the levels of stress that various parts of the dummies' bodies will endure. Such a "color map" could provide vital information to engineers designing safer automobiles.

Or imagine baseball gloves that when worn show the batters if they are using the appropriate amount of pressure to grip their bats, resulting in better performance.

New technology developed at the University of California, Riverside may now make the above and similar ideas a reality. Indeed, the technology could be applied to improve everyday devices, such as smartphones, that for operation rely on the right amount of pressure applied to them.

"We have developed a high-resolution pressure sensor that indicates pressure by varying its color -- a sensor that all of us can use with just our eyes," said Yadong Yin, an associate professor of chemistry, whose lab led the research.

The lab used a self-assembly method to string together gold nanoparticles which they then embedded into a polymer film. The film deformed when pressed, stretching the gold nanoparticle strings by increasing the separation between neighboring gold nanoparticles.

"This increased separation alters the way the nanoparticles interact with light," Yin explained. "When linked together, the gold nanoparticles originally appear blue. But they gradually change to red with increasing pressure as the nanoparticles start disassembling. This easily and visually helps us figure out how much pressure has been applied."

Study results appear this month in Nano Letters.

The sensor that Yin's lab developed differs from commercially available pressure sensor films. The latter indicate pressure by changing the intensity of just one color (for example, a pale red to a darker red). They tend to be difficult to interpret and have low resolution and contrast.

The new technology produces a mosaic of easy-to-distinguish colors and has the benefit of higher contrast and resolution. It can potentially be used in many safety devices for revealing pressure distribution over even very complex surfaces.

"The many electronic stress sensors commercially available are bulky and not suitable for certain applications," Yin said. "For example, it is difficult to tell the stress distribution over a particular area if the contact surfaces are not flat and uniform. Our sensor films can be painted on the contact surfaces so that the color variance in different areas clearly shows the stress distribution over the contact surface."

While his lab used gold in the experiments, silver and copper could also work, Yin added. The sensor the lab developed is a solid plastic film. Under stress, it deforms like conventional plastics. The new color that arises persists after the stress is removed.

"This is why we are calling it a 'colorimetric stress memory sensor,'" Yin said.

One of the research interests of his lab is the design of materials with new properties via the self-assembly process. The lab first makes nanoparticles and then organizes them together to produce new properties arising from particle-particle interactions.

"In the case of our sensor, we initially found a way to organize gold nanoparticles together to form strings," Yin said. "That process is accompanied by a sharp color-change from red to blue. We speculated that the reverse -- disassembly -- process might have the reverse color change: from blue to red. We found to our surprise that mechanical force could achieve this disassembly. Considerable effort has been made by researchers to study nanoparticle self-assembly. Indeed, gold nanoparticles have conventionally been used as sensors based on the self-assembly process. What is novel about our work is that it shows that the disassembly process can also find great applications if the assembly is designed to be reversible."

Yin was joined in the research by Xiaogang Han, a former postdoctoral researcher in his lab; and Yiding Liu, a graduate student who recently won the graduate student silver award at the Materials Research Society in San Francisco, Calif.

The research was funded by a grant to Yin from the National Science Foundation.


Story Source:

The above story is based on materials provided by University of California - Riverside. Note: Materials may be edited for content and length.


Journal Reference:

  1. Xiaogang Han, Yiding Liu, Yadong Yin. Colorimetric Stress Memory Sensor Based on Disassembly of Gold Nanoparticle Chains. Nano Letters, 2014; 140408153751001 DOI: 10.1021/nl500144k

Cite This Page:

University of California - Riverside. "New revolutionary sensor links pressure to color change." ScienceDaily. ScienceDaily, 30 April 2014. <www.sciencedaily.com/releases/2014/04/140430192753.htm>.
University of California - Riverside. (2014, April 30). New revolutionary sensor links pressure to color change. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2014/04/140430192753.htm
University of California - Riverside. "New revolutionary sensor links pressure to color change." ScienceDaily. www.sciencedaily.com/releases/2014/04/140430192753.htm (accessed September 2, 2014).

Share This




More Matter & Energy News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Australian Airlines Relax Phone Ban Too

Australian Airlines Relax Phone Ban Too

Reuters - Business Video Online (Aug. 26, 2014) Qantas and Virgin say passengers can use their smartphones and tablets throughout flights after a regulator relaxed a ban on electronic devices during take-off and landing. As Hayley Platt reports the move comes as the two domestic rivals are expected to post annual net losses later this week. Video provided by Reuters
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Chinese Researchers Might Be Creating Supersonic Submarine

Chinese Researchers Might Be Creating Supersonic Submarine

Newsy (Aug. 26, 2014) Chinese researchers have expanded on Cold War-era tech and are closer to building a submarine that could reach the speed of sound. Video provided by Newsy
Powered by NewsLook.com
Breakingviews: India Coal Strained by Supreme Court Ruling

Breakingviews: India Coal Strained by Supreme Court Ruling

Reuters - Business Video Online (Aug. 26, 2014) An acute coal shortage is likely to be aggravated as India's supreme court declared government coal allocations illegal, says Breakingviews' Peter Thal Larsen. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Flexible Pressure-Sensor Film Shows How Much Force a Surface 'feels' -- In Color

Apr. 30, 2014 A newly developed pressure sensor could help car manufacturers design safer automobiles and even help Little League players hold their bats with a better grip, scientists report. Their ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins