Nanotechnology Now





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

The Hydrogen-Fuel cell will revolutionize the economy of the world: New non-platinum and nanosized catalyst for polymer electrolyte fuel cell June 29th, 2015

June 29th, 2015

Efforts to Use Smart Nanocarriers to Cure Leukemia Yield Promising Results June 29th, 2015

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Chemistry

The Hydrogen-Fuel cell will revolutionize the economy of the world: New non-platinum and nanosized catalyst for polymer electrolyte fuel cell June 29th, 2015

Nanotubes/Buckyballs/Fullerenes

Cellulose from wood can be printed in 3-D June 17th, 2015

Researchers grind nanotubes to get nanoribbons: Rice-led experiments demonstrate solid-state carbon nanotube 'templates' June 15th, 2015

Environmental Issues to Hamper Growth of Global Nanocomposites Market June 4th, 2015

Carbon Nanotubes (CNT) Market Trends, Segments And Forecasts To 2022: Grand View Research, Inc June 1st, 2015

Announcements

The Hydrogen-Fuel cell will revolutionize the economy of the world: New non-platinum and nanosized catalyst for polymer electrolyte fuel cell June 29th, 2015

June 29th, 2015

Efforts to Use Smart Nanocarriers to Cure Leukemia Yield Promising Results June 29th, 2015

Making new materials with micro-explosions: ANU media release: Scientists have made exotic new materials by creating laser-induced micro-explosions in silicon, the common computer chip material June 29th, 2015

Research partnerships

June 29th, 2015

Graphene breakthrough as Bosch creates magnetic sensor 100 times more sensitive than silicon equivalent June 28th, 2015

The peaks and valleys of silicon: Team of USC Viterbi School of Engineering Researchers introduce new layered semiconducting materials as silicon alternative June 27th, 2015

Building a better semiconductor: Research led by Michigan State University could someday lead to the development of new and improved semiconductors June 27th, 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