Making sure the wonder materials don't become the wonder pollutant

April 08, 2008

Carbon nanotubes are 10,000 times thinner than a human hair, yet stronger than steel and more durable than diamonds. They conduct heat and electricity with efficiency that rivals copper wires and silicon chips, with possible uses in everything from concrete and clothes to bicycle parts and electronics. The have been hailed as the next "wonder material" for what could become a multi-billion dollar manufacturing industry in the 21st century.

But as useful as nanotubes may be, the process of making them may have unintentional and potentially harmful impacts on the environment. MIT/WHOI graduate student Desirée Plata and her mentors--chemists Phil Gschwend of the Massachusetts Institute of Technology and Chris Reddy of the Woods Hole Oceanographic Institution--recently analyzed ten commercially made carbon nanotubes to identify the chemical byproducts of the manufacturing process and to help track them in the environment.

Plata found that the ten different carbon nanotubes had vastly different compositions; most previous toxicity studies have generally assumed that all nanotubes are the same. This diversity of chemical signatures will make it harder to trace the impacts of carbon nanotubes in the environment

In previous work (first presented last fall), Plata and colleagues found that the process of nanotube manufacturing produced emissions of at least 15 aromatic hydrocarbons, including four different kinds of toxic polycyclic aromatic hydrocarbons (PAHs) similar to those found in cigarette smoke and automobile tailpipe emissions. They also found that the process was largely inefficient: much of the raw carbon went unconsumed and was vented into the atmosphere.

The new research by Plata et al was published April 3 on the web site of the journal Nanotechnology. In the next phase of Plata's work, she will collect real-time data from a European nanotube manufacturing facility that is poised to let her set up the same monitors she used in the MIT lab.

"It is the indiscriminant use of poorly understood chemicals that causes environmental and public health costs," Plata said. "We want to work proactively with the carbon nanotube industry to avoid repeating environmental mistakes of the past. Instead of reacting to problems, we hope to preclude them altogether."

Plata was honored in February for her nanotube work by the Division of Environmental Chemistry of the American Chemical Society, which selected her as a winner of one of its 2008 Graduate Student Paper Awards.
-end-


Woods Hole Oceanographic Institution

Related Carbon Nanotubes Articles from Brightsurf:

How plantains and carbon nanotubes can improve cars
Researchers from the University of Johannesburg have shown that plantain, a starchy type of banana, is a promising renewable source for an emerging type of lighter, rust-free composite materials for the automotive industry.

New production method for carbon nanotubes gets green light
A new method of producing carbon nanotubes -- tiny molecules with incredible physical properties used in touchscreen displays, 5G networks and flexible electronics -- has been given the green light by researchers, meaning work in this crucial field can continue.

Growing carbon nanotubes with the right twist
Researchers synthetize nanotubes with a specific structure expanding previous theories on carbon nanotube growth.

Research shows old newspapers can be used to grow carbon nanotubes
New research has found that old newspaper provide a cheap and green solution for the bulk production of single walled carbon nanotubes.

Clean carbon nanotubes with superb properties
Scientists at Aalto University, Finland, and Nagoya University, Japan, have found a new way to make ultra-clean carbon nanotube transistors with superior semiconducting properties.

Dietary fiber effectively purifies carbon nanotubes
A dietary fiber can help separate out semiconducting carbon nanotubes used for making transistors for flexible electronics.

Why modified carbon nanotubes can help the reproducibility problem
Scientists at Tokyo Institute of Technology (Tokyo Tech) conducted an in-depth study on how carbon nanotubes with oxygen-containing groups can be used to greatly enhance the performance of perovskite solar cells.

Tensile strength of carbon nanotubes depends on their chiral structures
Single-walled carbon nanotubes should theoretically be extremely strong, but it remains unclear why their experimental tensile strengths are lower and vary among nanotubes.

New study reveals carbon nanotubes measurement possible for the first time
Swansea University scientists report an entirely new approach to manipulation of carbon nanotubes that allows physical measurements to be made on carbon nanotubes that have previously only been possible by theoretical computation.

Neural networks will help manufacture carbon nanotubes
A team of scientists from Skoltech's Laboratory of Nanomaterials proposed a neural-network-based method for monitoring the growth of carbon nanotubes, preparing the ground for a new generation of sophisticated electronic devices.

Read More: Carbon Nanotubes News and Carbon Nanotubes Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.