Strengthening Fluids With Nanoparticles

February 19, 2008
Strengthening Fluids With Nanoparticles

The contact angle of a droplet of nanofluid solution changes when exposed to an electric field. Image Credit: Rensselaer/Borca-Tasciuc

Researchers at Rensselaer Polytechnic Institute have demonstrated that liquids embedded with nanoparticles show enhanced performance and stability when exposed to electric fields. The finding could lead to new types of miniature camera lenses, cell phone displays, and other microscale fluidic devices.

“This study may open up a new vista for using nanofluids in microscale and nanoscale actuator device applications,” said Theodorian Borca-Tasciuc, a professor of mechanical engineering at Rensselaer, who led the research project.

The manipulation of small volumes of liquid is critical for fluidic digital display devices, optical devices, and microelectromechanical systems (MEMS) such as lab-on-chip analysis systems. Most research into such systems has been conducted with regular liquids, but not nanofluids, which are liquids embedded with different nanoparticles. Nanofluids have been shown to exhibit some attractive properties, including enhanced heat transfer and capillary properties, as compared with regular, or pure, liquids.

Borca-Tasciuc’s team placed droplets of water-based solutions containing bismuth telluride nanoparticles onto a Teflon-coated silicon wafer. When an electric field was applied to the droplet, the researchers observed a strong change in the angle at which the droplet contacted the wafer. This change was much higher than that observed in liquids without the nanoparticles when tested under the same conditions.

“You use the same electrical field, but you get more change in shape with the nanofluid. We know the nanoparticles are critical in this process because without them the effect is much less strong,” Borca-Tasciuc said.

The ability to easily change the contact angle of droplets of nanofluids has potential applications for efficiently moving liquids in microsystems, creating new methods of focusing lenses in miniature cameras, or cooling computer chips. Borca-Tasciuc also envisions the research enabling new fully integrated micro- and nanoscale heat transfer systems that will not require a pump. “Our proof of concept really opens up many new exciting possibilities,” he said.

Borca-Tasciuc said his investigations into nanofluids are driven by sheer curiosity, and fostered by a strong interdisciplinary collaboration with Rensselaer Materials Science and Engineering Professor Ganapathiraman Ramanath.

“At first, we were curious to see what would happen if we introduced charged nanostructures — such as the ones we synthesize for exploring new cooling strategies in nanodevices — to the process of liquid wetting. But what started as a single, one-off experiment has now mushroomed into an exciting new research topic and expanded the scope of our collaboration,” Ramanath said.

The research article, titled “Electrowetting on dielectric-actuation of microdroplets of aqueous bismuth telluride nanoparticle suspensions,” was published in a recent issue of the journal Nanotechnology.

Along with Borca-Tasciuc and Ramanath, co-authors of the paper include Rensselaer post-doctoral research associate Arup Purkayastha, and graduate student Raj K. Dash.

Source: Rensselaer Polytechnic Institute

4.3 /5 (16 votes)  

Filter


Move the slider to adjust rank threshold, so that you can hide some of the comments.


Display comments: newest first

holoman
Feb 24, 2008

Rank: not rated yet
bismuth telluride nanoparticles are multiferroic

UPR/UA have shown electric field polarity can influence multiferroic nanoparticle geometry which can be permanetly changed when photon irradiation is applied at the sametime as the field.

Rank 4.3 /5 (16 votes)
Tags

Relevant PhysicsForums posts

More news stories

Lab study raises questions over nano-particle impact

Tests involving chickens have raised questions about the impact on health from engineered nano-particles, the ultra-fine grains commonly used in drugs and processed foods, scientists said on Sunday.

Nanotechnology / Bio & Medicine

created 12 minutes ago | popularity 5 / 5 (1) | comments 0

New kind of solar cell could capture significantly more energy than current cells

New solar cells could increase the maximum efficiency of solar panels by over 25%, according to scientists from the University of Cambridge.

Nanotechnology / Nanophysics

created Feb 08, 2012 | popularity 4.5 / 5 (13) | comments 14 | with audio podcast

Nanoshell whispering galleries improve thin solar panels

Visitors to Statuary Hall in the U.S. Capitol Building may have experienced a curious acoustic feature that allows a person to whisper softly at one side of the cavernous, half-domed room and for another on ...

Nanotechnology / Nanomaterials

created Feb 07, 2012 | popularity 4.4 / 5 (7) | comments 6 | with audio podcast

'Dark plasmons' transmit energy

Microscopic channels of gold nanoparticles have the ability to transmit electromagnetic energy that starts as light and propagates via "dark plasmons," according to researchers at Rice University.

Nanotechnology / Nanophysics

created Feb 09, 2012 | popularity 4.8 / 5 (10) | comments 1 | with audio podcast

Revealing how a battery material works

Since its discovery 15 years ago, lithium iron phosphate (LiFePO4) has become one of the most promising materials for rechargeable batteries because of its stability, durability, safety and ability to deliver ...

Nanotechnology / Nanomaterials

created Feb 08, 2012 | popularity 5 / 5 (6) | comments 0 | with audio podcast


Scientists discover molecular secrets of 2,000-year-old Chinese herbal remedy

For roughly two thousand years, Chinese herbalists have treated Malaria using a root extract, commonly known as Chang Shan, from a type of hydrangea that grows in Tibet and Nepal. More recent studies suggest that halofuginone, ...

New method to examine batteries -- MRI from the inside

There is an ever-increasing need for advanced batteries for portable electronics, such as phones, cameras, and music players, but also to power electric vehicles and to facilitate the distribution and storage of energy derived ...

A mitosis mystery solved: How chromosomes align perfectly in a dividing cell

Although the process of mitotic cell division has been studied intensely for more than 50 years, Whitehead Institute researchers have only now solved the mystery of how cells correctly align their chromosomes during symmetric ...

Starve a virus, feed a cure? Findings show how some cells protect themselves against HIV

A protein that protects some of our immune cells from the most common and virulent form of HIV works by starving the virus of the molecular building blocks that it needs to replicate, according to research published online ...

Researchers find extensive RNA editing in human transcriptome

In a new study published online in Nature Biotechnology, researchers from BGI, the world's largest genomics organization, reported the evidence of extensive RNA editing in a human cell line by analysis of RNA-seq data, demons ...

The proteins ensuring genome protection

Researchers from the University of Geneva (UNIGE), Switzerland, have discovered the crucial role of two proteins in developing a cell 'anti-enzyme shield'. This protection system, which operates at the level of molecular ...