Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Intricate, curving 3D nanostructures created using capillary action forces

By using unique two-dimensional templates, researchers at the University of Michigan could 
coax carbon nanotubes to grow in intricate, curving three-dimensional structures. Credit: A. John Hart
By using unique two-dimensional templates, researchers at the University of Michigan could coax carbon nanotubes to grow in intricate, curving three-dimensional structures. Credit: A. John Hart

Abstract:
Twisting spires, concentric rings, and gracefully bending petals are a few of the new three-dimensional shapes that University of Michigan engineers can make from carbon nanotubes using a new manufacturing process.

Intricate, curving 3D nanostructures created using capillary action forces

Ann Arbor, MI | Posted on October 22nd, 2010

The process is called "capillary forming," and it takes advantage of capillary action, the phenomenon at work when liquids seem to defy gravity and spontaneously travel up a drinking straw.

The new miniature shapes have the potential to harness the exceptional mechanical, thermal, electrical, and chemical properties of carbon nanotubes in a scalable fashion, said A. John Hart, an assistant professor in the Department of Mechanical Engineering and in the School of Art & Design.

The 3D nanotube structures could enable countless new materials and microdevices, including probes that can interface with individual cells, novel microfluidic devices, and lightweight materials for aircraft and spacecraft.

A paper on the research is published in the October edition of Advanced Materials, and is featured on the cover.

"It's easy to make carbon nanotubes straight and vertical like buildings," Hart said. "It hasn't been possible to make them into more complex shapes. Assembling nanostructures into three-dimensional shapes is one of the major goals of nanotechnology and nanomanufacturing. The method of capillary forming could be applied to many types of nanotubes and nanowires, and its scalability is very attractive for manufacturing."

Hart's method starts by patterning a thin metal film on a silicon wafer. This film is the iron catalyst that facilitates the growth of vertical carbon nanotube "forests" in patterned shapes. It's a sort of template. Rather than pattern the catalyst into uniform shapes such as circles and squares, Hart's team patterns a variety of unique shapes such as hollow circles, half circles, and circles with smaller ones cut from their centers. The shapes are arranged in different orientations and groupings, creating different templates for later forming the 3D structures using capillary action.

He uses a chemical vapor deposition process to grow the nanotubes in the prescribed patterns. Chemical vapor deposition involves heating the substrate with the catalyst pattern in a high temperature furnace containing a hydrocarbon gas mixture. The gas reacts over the catalyst, and the carbon from the gas is converted into nanotubes, which grow upward like grass.

Then he suspends the silicon wafer with its nanotubes over a beaker of a boiling acetone. He lets the acetone condense on the nanotubes, and then evaporate.

As the liquid condenses, it travels upward into the spaces among the vertical nanotubes. Capillary action kicks in and transforms the vertical nanotubes into the intricate three-dimensional structures. For example, tall half-cylinders of nanotubes bend backwards to form a shape resembling a three-dimensional flower.

"We program the formation of 3D shapes with these 2D patterns," Hart said. "We've discovered that the starting shape influences how the capillary forces manipulate the nanotubes in a very specific way. Some bend, others twist, and we can combine them any way we want."

The capillary forming process allows the researchers to create large batches of 3D microstructures—all much smaller than a cubic millimeter, Hart said. In addition, the researchers show that their 3D structures are up to 10 times stiffer than typical polymers used in microfabrication. Thus, they can be used as molds for manufacturing of the same 3D shapes in other materials.

"We think this opens up the possibility to create custom nanostructured surfaces and materials with locally varying geometries and properties, " Hart said. "Before, we thought of materials as having the same properties everywhere, but with this new technique we can dream of designing the structure and properties of a material together."

The paper is called "Diverse 3D Microarchitectures Made by Capillary Forming of Carbon Nanotubes," The lead authors are postdoctoral researcher Michael De Volder, and Sameh Tawfick, a doctoral candidate in Mechanical Engineering.

This research is funded by the University of Michigan College of Engineering and the U-M Department of Mechanical Engineering, the Belgium Fund for Scientific Research, and the National Science Foundation.

The university is pursuing patent protection for the intellectual property, and is seeking commercialization partners to help bring the technology to market.

####

For more information, please click here

Contacts:
Nicole Casal Moore
Phone: (734) 647-7087

Copyright © University of Michigan

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Scientists find a way of acquiring graphene-like films from salts to boost nanoelectronics: Physicists use supercomputers to find a way of making 'imitation graphene' from salt July 30th, 2016

Vortex laser offers hope for Moore's Law: The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold July 30th, 2016

New method for making green LEDs enhances their efficiency and brightness July 30th, 2016

A new type of quantum bits July 29th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Vortex laser offers hope for Moore's Law: The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold July 30th, 2016

A new type of quantum bits July 29th, 2016

Thomas Swan and NGI announce unique partnership July 28th, 2016

Penn team uses nanoparticles to break up plaque and prevent cavities July 28th, 2016

Possible Futures

Scientists find a way of acquiring graphene-like films from salts to boost nanoelectronics: Physicists use supercomputers to find a way of making 'imitation graphene' from salt July 30th, 2016

Vortex laser offers hope for Moore's Law: The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold July 30th, 2016

New method for making green LEDs enhances their efficiency and brightness July 30th, 2016

Novel state of matter: Observation of a quantum spin liquid July 29th, 2016

Academic/Education

Thomas Swan and NGI announce unique partnership July 28th, 2016

The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016

News from Quorum: The College of New Jersey use the Quorum Cryo-SEM preparation system in a project to study ice crystals in high altitude clouds July 19th, 2016

Leti and Korea Institute of Science and Technology to Explore Collaboration on Advanced Technologies for Digital Era July 14th, 2016

Nanotubes/Buckyballs/Fullerenes

Easier, faster, cheaper: A full-filling approach to making nanotubes of consistent quality: Approach opens a straightforward route for engineering the properties of single-wall carbon nanotubes July 19th, 2016

Sensing trouble: A new way to detect hidden damage in bridges, roads: University of Delaware engineers devise new method for monitoring structural health July 8th, 2016

Wireless, wearable toxic-gas detector: Inexpensive sensors could be worn by soldiers to detect hazardous chemical agents July 4th, 2016

Nanotubes' 'stuffing' as is: A scientist from the Lomonosov Moscow State University studied the types of carbon nanotubes' 'stuffing' June 2nd, 2016

Nanomedicine

Scientists change properties of zeolites to improve hemodialysis July 29th, 2016

Pixel-array quantum cascade detector paves the way for portable thermal imaging devices: Research team from TU-Wien Center for Micro- and Nanostructures have developed a new 'cooler' sensing instrument thereby increasing energy-efficiency and enhancing mobility for diagnostic tes July 28th, 2016

Starpharma initiates new DEP™ drug delivery program with AstraZeneca July 27th, 2016

Scientists test nanoparticle drug delivery in dogs with osteosarcoma July 26th, 2016

Announcements

Scientists find a way of acquiring graphene-like films from salts to boost nanoelectronics: Physicists use supercomputers to find a way of making 'imitation graphene' from salt July 30th, 2016

Vortex laser offers hope for Moore's Law: The optics advancement may solve an approaching data bottleneck by helping to boost computing power and information transfer rates tenfold July 30th, 2016

New method for making green LEDs enhances their efficiency and brightness July 30th, 2016

A new type of quantum bits July 29th, 2016

Patents/IP/Tech Transfer/Licensing

Starpharma initiates new DEP™ drug delivery program with AstraZeneca July 27th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Research team led by NUS scientists develop plastic flexible magnetic memory device: Novel technique to implant high-performance magnetic memory chip on a flexible plastic surface without compromising performance July 21st, 2016

New nanoscale technologies could revolutionize microscopes, study of disease July 20th, 2016

Aerospace/Space

Scientists move 1 step closer to creating an invisibility cloak July 15th, 2016

Bouncing droplets remove contaminants like pogo jumpers: Researchers at Duke University and the University of British Columbia are exploring whether surfaces can shed dirt without being subjected to fragile coatings July 7th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Novel capping strategy improves stability of perovskite nanocrystals: Study addresses instability issues with organometal-halide perovskites, a promising class of materials for solar cells, LEDs, and other applications June 13th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic