Scientists uncover chemical transformations in cobalt nanoparticles

May 24, 2011 By Anne Ju
Scientists unveil transformations in cobalt
The evolution schematics of transition from cobalt to cobalt phosphide nanocrystals.

Understanding the intricacies of how nanoparticles undergo chemical transformations could lead to better ways to tailor their composition, which can lead to advanced material properties.

Using the Cornell High Energy Synchrotron Source, scientists led by Richard Robinson, assistant professor of materials science and engineering, uncovered exactly what happens when cobalt nanoparticles transform into two phases of cobalt phosphides.

Their work, published in the , was featured by the journal as a "Hot Article" earlier this month.

The effect Robinson's team observed in the cobalt transitions was a nanoparticle hollowing due to asymmetric diffusivities of cations and anions. In other words, the cations move out from the core faster than anions can diffuse in, leading to a hollow particle.

Other groups have reported on this "Kirkendall" effect, but the Robinson team was the first to show that this hollowing is more complex than previously thought and can be studied as a two-step process. Their work could be used to control this process and produce complex particles with properties tailored for use in energy applications. Metal phosphides have a wide range of properties -- ferromagnetism, superconductivity, catalytic activity and among them.

The work was done in collaboration with scientists led by Richard Hennig, assistant professor of materials science and engineering. It was supported by King Abdullah University of Science and Technology, the Cornell Center for Materials Research and the Center at Cornell.

Explore further: Shape matters in the case of cobalt nanoparticles

Related Stories

Shape matters in the case of cobalt nanoparticles

June 17, 2009

Shape is turning out to be a particularly important feature of some commercially important nanoparticles—but in subtle ways. New studies* by scientists at the National Institute for Standards and Technology (NIST) show ...

Size matters in crucial redox reactions

October 12, 2010

(PhysOrg.com) -- Particle size has a far more dramatic impact on chemical reactivity than previously thought, according to new research from UC Davis. The results have implications for understanding a wide range of vital ...

Platinum-coated nanoparticles could lead to better fuel cells

December 9, 2010

(PhysOrg.com) -- Fuel cells may power the cars of the future, but it's not enough to just make them work -- they have to be affordable. Cornell researchers have developed a novel way to synthesize a fuel cell electrocatalytic ...

Recommended for you

Brazilian wasp venom kills cancer cells by opening them up

September 1, 2015

The social wasp Polybia paulista protects itself against predators by producing venom known to contain a powerful cancer-fighting ingredient. A Biophysical Journal study published September 1 reveals exactly how the venom's ...

Water heals a bioplastic

September 1, 2015

A drop of water self-heals a multiphase polymer derived from the genetic code of squid ring teeth, which may someday extend the life of medical implants, fiber-optic cables and other hard to repair in place objects, according ...

Naturally-occurring protein enables slower-melting ice cream

August 31, 2015

(Phys.org)—Scientists have developed a slower-melting ice cream—consider the advantages the next time a hot summer day turns your child's cone with its dream-like mound of orange, vanilla and lemon swirls with chocolate ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.