Nav: Home

Nanoparticles can grow in cubic shape

April 04, 2016

The efficiency of many applications deriving from natural sciences depends dramatically on a finite-size property of nanoparticles, so-called surface-to-volume ratio. The larger the surface of nanoparticles for the same volume is achieved, the more efficiently nanoparticles can interact with the surrounding substance. However, thermodynamic equilibrium forces nanostructures to minimize open surface driven by energy minimization principle. This basic principle predicts that the only shape of nanoparticles can be spherical or close-to-spherical ones.

Nature, however, does not always follow the simple principles. An intensive collaboration between University of Helsinki, Finland, and Okinawa Institute of Science and Technology, Japan, showed that in some condition iron nanoparticles can grow in cubic shape. The scientists also succeeded in disclosing the mechanisms behind this.

"Now we have a recipe how to synthesize cubic shapes with high surface-to-volume ratio which opens the door for practical applications", says Dr. Flyura Djurabekova from the University of Helsinki.

In the researcher's work, experiment and theory were brought together via a new mathematical model, which gives a recipe on how to select macroscopic experimental conditions to achieve the formation of nanoparticles of desired shape.

The computational work carried out in the group of Djurabekova showed the importance of kinetical processes in this surprising phenomenon, namely the competition between surface diffusion and deposition rate of atoms. The simulations showed how an originally spherical nucleus transforms into a perfect cube.

The results were recently published in the high-impact factor journal ACS Nano.

-end-

Junlei Zhao, Ekaterina Baibuz, Jerome Vernieres, Panagiotis Grammatikopoulos, Ville Jansson, Morten Nagel, Stephan Steinhauer, Mukhles Sowwan, Antti Kuronen, Kai Nordlund, and Flyura Djurabekova, Formation Mechanism of Fe Nanocubes by Magnetron Sputtering Inert Gas Condensation, ACS Nano, Article ASAP, DOI: 10.1021/acsnano.6b01024, Publication Date (Web): March 10, 2016, Copyright © 2016 American Chemical Society

http://pubs.acs.org/doi/suppl/10.1021/acsnano.6b01024

Image text: Originally close-to-spherical iron nanoparticle nuclei grow in magnetron sputter chambers either cubic or spheres. The research revealed a specific regime of temperature and deposition rates leading to thermodynamically unexpected cubic shapes of final nanoparticles.

Image: Panagiotis Grammatikopoulos, Okinawa Institute for Science and Technology

For more information:

Dr. Flyura Djurabekova, Department of Physics, University of Helsinki, +358-(0)2941-50084, flyura. djurabekova@helsinki.fi

With kind regards,
Minna Meriläinen-Tenhu, Press Officer, University of Helsinki, @MinnaMeriTenhu, +358 50 415 0316, minna.merilainen@helsinki.fi

University of Helsinki

Related Nanoparticles Articles:

Chemists perform surgery on nanoparticles
A team of chemists led by Carnegie Mellon's Rongchao Jin has for the first time conducted site-specific surgery on a nanoparticle.
Nanoparticles remain unpredictable
The way that nanoparticles behave in the environment is extremely complex.
Gold standards for nanoparticles
KAUST researchers reveal how small organic 'citrate' ions can stabilize gold nanoparticles, assisting research on the structures' potential.
Lipid nanoparticles for gene therapy
Twenty-five years have passed since the publication of the first work on solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) as a system for delivering drugs.
Nanoparticles hitchhiking their way along strands of hair
In shampoo ads, hair always looks like a shiny, smooth surface.
Better contrast agents based on nanoparticles
Scientists at the University of Basel have developed nanoparticles which can serve as efficient contrast agents for magnetic resonance imaging.
Gentle cancer treatment using nanoparticles works
Cancer treatments based on laser irridation of tiny nanoparticles that are injected directly into the cancer tumor are working and can destroy the cancer from within.
Radiation-guided nanoparticles zero in on metastatic cancer
Zap a tumor with radiation to trigger expression of a molecule, then attack that molecule with a drug-loaded nanoparticle.
Nanoparticles can grow in cubic shape
Use of nanoparticles in many applications, e.g. for catalysis, relies on the surface area of the particles.
Nanoparticles deliver anticancer cluster bombs
Scientists have devised a triple-stage 'cluster bomb' system for delivering the chemotherapy drug cisplatin, via tiny nanoparticles designed to break up when they reach a tumor.

Best Science Podcasts 2017

We have hand picked the best science podcasts for 2017. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: Radiolab

Oliver Sipple
One morning, Oliver Sipple went out for a walk. A couple hours later, to his own surprise, he saved the life of the President of the United States. But in the days that followed, Sipple's split-second act of heroism turned into a rationale for making his personal life into political opportunity. What happens next makes us wonder what a moment, or a movement, or a whole society can demand of one person. And how much is too much?  Through newly unearthed archival tape, we hear Sipple himself grapple with some of the most vexing topics of his day and ours - privacy, identity, the freedom of the press - not to mention the bonds of family and friendship.  Reported by Latif Nasser and Tracie Hunte. Produced by Matt Kielty, Annie McEwen, Latif Nasser and Tracie Hunte. Special thanks to Jerry Pritikin, Michael Yamashita, Stan Smith, Duffy Jennings; Ann Dolan, Megan Filly and Ginale Harris at the Superior Court of San Francisco; Leah Gracik, Karyn Hunt, Jesse Hamlin, The San Francisco Bay Area Television Archive, Mike Amico, Jennifer Vanasco and Joey Plaster. Support Radiolab today at Radiolab.org/donate.
Now Playing: TED Radio Hour

Future Consequences
From data collection to gene editing to AI, what we once considered science fiction is now becoming reality. This hour, TED speakers explore the future consequences of our present actions. Guests include designer Anab Jain, futurist Juan Enriquez, biologist Paul Knoepfler, and neuroscientist and philosopher Sam Harris.