Crazy carbon nanofoam loves magnets
Tiny particles of carbon that look like sooty foam and attract magnets have been made by Australian scientists.
This new form of carbon nanoparticle, called nanofoam, surprised the researchers as it was the first type of carbon to have magnetic properties.
The researchers made this new form of carbon using a laser system that fired up to 76 million pulses a second at graphite in a chamber filled with argon gas.
At 10,000°C the graphite evaporated into single carbon atoms, which settled into clusters as the vapour cooled.
The clusters then combined to form the spongy nanofoam, a cross between diamond and graphite.
"It's not diamond and it's not graphite. It's something in between," Rode told ABC Science Online. "It looks like a soot and it's very light."
The researchers also found that the new substance was attracted to magnets, an unusual property for carbon.
"We discovered the nanofoam has very strange magnetic properties which we didn't expect at all," said Rode.
The researchers made the nanofoam accidentally, as a byproduct in experiments involving the production of other forms of carbon, namely carbon nanotubes and buckyballs or carbon atoms arranged in a sphere.
Rode said there were no immediate applications for the new magnetic nanofoam but it could be useful in medicine.
"We can dream about the possibility of injecting such carbon nanofoam into blood, for example," he said. "Its magnetic properties would increase significantly the resolution of magnetic resonance imaging."
He said nanofoam could also be attached to tumours and be exposed to high frequency electromagnetic fields that would produce tumour-killing heat.
"This is pure speculation at this time, it's just one of the possibilities."
Rode said he was unable to comment on concerns about possible health and environmental effects of tiny nanoparticles.
"I've heard about such concerns but to answer this question you need special research done by biologists, medical people and physicists at the same time," he said.