Navigation Links
Scientists glimpse nanobubbles on super nonstick surfaces
Date:2/26/2010

UPTON, NY Scientists at the U.S. Department of Energy's Brookhaven National Laboratory have obtained the first glimpse of miniscule air bubbles that keep water from wetting a super non-stick surface. Detailed information about the size and shape of these bubbles and the non-stick material the scientists created by "pock-marking" a smooth material with cavities measuring mere billionths of a meter is being published online today in the journal Nano Letters.

"Our results explain how these nanocavities trap tiny bubbles which render the surface extremely water repellent," said Brookhaven physicist and lead author Antonio Checco. The research could lead to a new class of non-stick materials for a range of applications, including improved-efficiency power plants, speedier boats, and surfaces that are resistant to contamination by germs.

Non-stick surfaces are important to many areas of technology, from drag reduction to anti-icing agents. These surfaces are usually created by applying coatings, such as Teflon, to smooth surfaces. But recently taking the lead from observations in nature, notably the lotus leaf and some varieties of insects scientists have realized that a bit of texture can help. By incorporating topographical features on surfaces, they've created extremely water repellant materials.

"We call this effect 'superhydrophobicity,'" said Brookhaven physicist Benjamin Ocko. "It occurs when air bubbles remain trapped in the textured surfaces, thereby drastically reducing the area of liquid in contact with the solid." This forces the water to ball up into pearl shaped drops, which are weakly connected to the surface and can readily roll off, even with the slightest incline.

"To get the first glimpse of nanobubbles on a superhydrophobic surface we created a regular array of more than a trillion nano-cavities on an otherwise flat surface, and then coated it with a wax-like surfactant," said Charles Black, a physicist at Brookhaven's [http://www.bnl.gov/cfn/] Center for Functional Nanometerials .

This coated, nanoscale textured surface was much more water repellant than the flat surface alone, suggesting the existence of nanobubbles. However, because the nanoscale is not accessible using ordinary microscopes, little is known about these nanobubbles.

To unambiguously prove that these ultra-small bubbles were present, the Brookhaven team carried out x-ray measurements at the [http://www.nsls.bnl.gov] National Synchrotron Light Source . "By watching how the x-rays diffracted, or bounced off the surface, we are able to image extremely small features and show that the cavities were mostly filled with air," said Brookhaven physicist Elaine DiMasi.

Checco added, "We were surprised that water penetrates only about 5 to 10 nanometers into the cavities an amount corresponding to only 15 to 30 layers of water molecules independent of the depth of the cavities. This provides the first direct evidence of the morphology of such small bubbles."

According to the scientists' observations, the bubbles are only about 10 nanometers in size about ten thousand times smaller than the width of a single human hair. And the team's results conclusively show that these tiny bubbles have nearly flat tops. This is in contrast to larger, micrometer-sized bubbles, which have a more rounded top.

"This flattened configuration is appealing for a range of applications because it is expected to increase hydrodynamic slippage past the nanotextured surface," Checco said. "Moreover, the fact that water hardly penetrates into the nano-textures, even if an external pressure is applied to the liquid, implies that these nanobubbles are very stable."

Therefore, in contrast to materials with larger, micrometer-sized textures, the surfaces fabricated by the Brookhaven team may exhibit more stable superhydrophobic properties.

"These findings provide a better understanding of the nanoscale aspects of superhydropobicity, which should help to improve the design of future superhydrophobic non-stick surfaces," Checco said.


'/>"/>

Contact: Karen McNulty Walsh
kmcnulty@bnl.gov
631-344-8350
DOE/Brookhaven National Laboratory
Source:Eurekalert

Related biology technology :

1. Princeton scientists find an equation for materials innovation
2. Scientists glimpse nanobubbles on super non-stick surfaces
3. Scientists transplant nose of mosquito, advance fight against malaria
4. Penn material scientists turn light into electrical current using a golden nanoscale system
5. Seeing the quantum in chemistry: JILA scientists control chemical reactions of ultracold molecules
6. NFCR Scientists Discover Brain Tumor's “Escape Path”
7. Scientists achieve first rewire of genetic switches
8. Scientists create worlds first molecular transistor
9. 6 PNNL scientists elected AAAS fellows
10. Particle Size Distribution Technologies at American Association of Pharmaceutical Scientists (AAPS) Annual Meeting 2010
11. Argonne Scientists Use Bacteria to Power Simple Machines
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/22/2017)... , Feb. 22, 2017 Origin (Origin Agritech, LLC, a ... and seed provider, and Arcadia (Arcadia Biosciences, ... develops and commercializes agricultural productivity traits and nutritional products, today announced ... biotechnology product developed in China to ... trials. ...
(Date:2/22/2017)... PHOENIX and SAN DIEGO ... Technology Holdings (the "Company") (OTCQB:CELZ) announced today expansion ... universal donor stem cell product through establishment of ... initiated research activities at the San Diego BioLabs ... Companies, Boehringer Ingelheim, Novartis, and Sanofi. ...
(Date:2/21/2017)... (PRWEB) , ... February 21, 2017 , ... ... healthcare organizations to build connected digital health applications, announced a partnership with Redox, ... users to seamlessly connect to many clinical systems while keeping data secure in ...
(Date:2/21/2017)... , ... February 21, 2017 , ... The medical potential ... their use, in multiple areas of medicine, due to their differentiating characteristics. Stem cells ... they have the ability to be induced to become tissue or organic-specific cells with ...
Breaking Biology Technology:
(Date:2/7/2017)... Feb. 7, 2017 Zimmer Biomet Holdings, Inc. ... healthcare, will present at the LEERINK Partners 6th Annual ... Hotel on Wednesday, February 15, 2017 at 10 a.m. ... the presentation can be accessed at http://wsw.com/webcast/leerink28/zbh .  ... conference via Zimmer Biomet,s Investor Relations website at ...
(Date:2/2/2017)...   TapImmune, Inc. (NASDAQ: ... the development of innovative peptide and gene-based immunotherapeutics ... metastatic disease, announced today it has successfully completed ... second clinical lot of TPIV 200, the company,s ... manufactured vaccine product will be used to supply ...
(Date:1/30/2017)... , Jan. 30, 2017   Invitae Corporation ... fastest growing genetic information companies, today announced that it ... results and provide 2017 guidance on Monday, February 13, ... call that day at 4:45 p.m. Eastern / 1:45 ... management team will briefly review financial results, guidance, and ...
Breaking Biology News(10 mins):