Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Nano-infused filters prove effective

Nanotubes grown in holes in silicon dioxide wafers have the potential to outperform currently available filters for many uses, Rice researchers found.
Nanotubes grown in holes in silicon dioxide wafers have the potential to outperform currently available filters for many uses, Rice researchers found.

Abstract:
Rice scientists build better catalyst with nanotube membranes

Nano-infused filters prove effective

Houston, TX | Posted on April 27th, 2010

Rice University researchers and their colleagues in Finland and Hungary have found a way to make carbon nanotube membranes that could find wide application as extra-fine air filters and as scaffolds for catalysts that speed chemical reactions.

The results reported in the journal ACS Nano show how such filters can remove up to 99 percent of particulates with diameters of less than a micrometer - or a millionth of a meter. (A human hair is about 100 micrometers wide.)

Using chemical vapor deposition (CVD), a team led by Rice's Robert Vajtai, a faculty fellow in mechanical engineering and materials science, created devices that, at the start of the process, look like tiny showerheads. After 30 minutes in the CVD furnace, the laser-created holes in these silicon dioxide templates fill up with a forest of carbon nanotubes through which only particles on the nanometer scale can pass.

When the tubes are functionalized with catalytic chemicals, particles enter one side of the filter in one form and come out as another. The process is similar to that used by catalytic converters in cars, which convert carbon monoxide into a less-toxic mix of carbon dioxide, nitrogen and water.

"Even when the holes are larger than the particle itself, it can be a very effective filter," Vajtai said. "The basic idea is you have this carbon nanotube forest. The gas flows through, and because of the very small distance between the tubes, gas atoms have to hit many of them before they get out the other side.

"This very strong interaction, compared to macroscopic materials and even some microscopic materials, provides a very good way to make a catalyst template or a filter that is much more effective than a HEPA (high-efficiency particulate-absorbing) filter you can buy at the store," he said.

The filters' permeability depends strongly on how long the nanotubes are allowed to grow, which determines their length and density. The team tested the filters' ability to act as catalysts by depositing palladium onto the nanotubes and using them to turn propene into propane, a benchmark test for catalysis. They found the activated membranes "showed excellent and durable activity," according to the paper.

Co-authors of the paper include Pulickel Ajayan, Rice's Benjamin M. and Mary Greenwood Anderson Professor in Mechanical Engineering and Materials Science and of chemistry; primary author Niina Halonen, Aatto Rautio, Anne-Riikka Leino, Teemu Kyllönen, Jyrki Lappalainen, Krisztiçn Kordás, Géza Tóth, Mike Huuhtanen and Riitta Keiski of the University of Oulu, Finland; and András Sápi, Mária Szabó, Ákos Kukovecz, Zoltán Kónya and Imre Kiricsi of the University of Szeged, Hungary. Funding came from Rice University, Tekes, the Finnish Funding Agency for Technology and Innovation, and the Academy of Finland.

####

For more information, please click here

Contacts:
David Ruth
Director of National Media Relations
Rice University
Office: 713-348-6327
Cell: 612-702-9473

Copyright © Rice University

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

Laboratorial Performance of Nanocomposite Membrane Improved in Water Purification July 28th, 2015

Perfect Optical Properties in Production of Aluminum Oxide Colloid Nanoparticles July 28th, 2015

Short wavelength plasmons observed in nanotubes: Berkeley Lab researchers create Ludinger liquid plasmons in metallic SWNTs July 28th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Chemistry

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Quantum networks: Back and forth are not equal distances! July 28th, 2015

Make mine a decaf: Breakthrough in knowledge of how nanoparticles grow: University of Leicester and CNRS researchers observe how nanoparticles grow when exposed to helium July 23rd, 2015

Nanotubes/Buckyballs/Fullerenes

Short wavelength plasmons observed in nanotubes: Berkeley Lab researchers create Ludinger liquid plasmons in metallic SWNTs July 28th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

UT Dallas nanotechnology research leads to super-elastic conducting fibers July 24th, 2015

Nano-C Receives EPA Approvals for Single Walled Carbon Nanotubes July 21st, 2015

Announcements

Laboratorial Performance of Nanocomposite Membrane Improved in Water Purification July 28th, 2015

Perfect Optical Properties in Production of Aluminum Oxide Colloid Nanoparticles July 28th, 2015

Short wavelength plasmons observed in nanotubes: Berkeley Lab researchers create Ludinger liquid plasmons in metallic SWNTs July 28th, 2015

'Seeing' molecular interactions could give boost to organic electronics July 28th, 2015

Research partnerships

Spintronics: Molecules stabilizing magnetism: Organic molecules fixing the magnetic orientation of a cobalt surface/ building block for a compact and low-cost storage technology/ publication in Nature Materials July 25th, 2015

Stretching the limits on conducting wires July 25th, 2015

Ultra-thin hollow nanocages could reduce platinum use in fuel cell electrodes July 24th, 2015

UT Dallas nanotechnology research leads to super-elastic conducting fibers July 24th, 2015

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