Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Efficient Production Process for Coveted Nanocrystals

A formation mechanism of nanocrystalline cerium dioxide (CeO2), a versatile nanomaterial, has been unveiled by scientists from the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) and the University of New South Wales in Sydney, Australia.

The research results were published in the scientific journal Chemistry – A European Journal (DOI: 10.1002/chem.201204101). This finding potentially simplifies and alleviates the existing synthetic processes of nanocrystalline CeO2 production.

Ce(IV) dimers and trimers form in aqueous solution nanometer-sized cer dioxide crystals (CeO2). The size of the nanocrystals is in the order of two to three nanometers.
Picture: A. Ikeda-Ohno

Nanocrystalline CeO2 particles are widely used, for example, in catalysts for hazardous gas treatment, in electrodes for solid oxide fuel cells, in polishing materials for advanced integrated circuits, in sunscreen cosmetics, and in such medical applications as artificial superoxide dismutase. Current industrial syntheses of nanocrystalline CeO2 are based on sol-gel processes followed by thermal treatment and/or the addition of accelerant reagents. Any further improvement of the synthetic strategy for CeO2 nanocrystals requires a better understanding of the mechanisms involved in their formation at the atomic scale.

Dr. Atsushi Ikeda-Ohno from the University of New South Wales, Australia, together with Dr. Christoph Hennig from the HZDR opted for a sophisticated multi-spectroscopic approach that combines dynamic light scattering and synchrotron-based X-ray techniques. These complex investigations involved the use of two world-leading synchrotron facilities of the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, and SPring-8 in Hyogo, Japan.

Live Monitoring

For the first time ever, the scientists were able to perform an in-situ observation of nanocrystal evolution. So far, little has been known of the formation mechanism of metal nanocrystals; mainly because appropriate analytical techniques were lacking. The most widely used techniques for metal nanocrystal research are electron microscopy and X-ray diffraction. They are powerful enough to visualize the appearance of nanocrystals and to acquire their lattice information, but they are not applicable to the solution state where the evolution of metal nanocrystals occurs. “To probe the formation of nanocrystalline CeO2 in an aqueous solution, we combined different spectroscopic techniques, including dynamic light scattering, synchrotron X-ray absorption spectroscopy, and high energy X-ray scattering,” says Dr. Atsushi Ikeda-Ohno.

The information the researchers obtained is fundamental to simplifying and alleviating the synthetic process of CeO2 nanocrystals. They revealed that uniformly sized nanoparticles of CeO2 can be produced simply by pH adjustment of tetravalent cerium (Ce(IV)) in an aqueous solution without subsequent physical/chemical treatment such as heating or adding accelerant chemicals. The produced CeO2 crystals have a uniform particle size of 2 - 3 nanometers, irrespective of the preparation conditions (e.g. pH and type of pH adjustment). This particle size is exactly in the range which is interesting for industrial applications. A key finding is that mononuclear Ce(IV) solution species do not result in nano-sized CeO2 crystals. The prerequisite is the presence of oligomeric Ce(IV) solution species, such as dimers or trimers.

“We’re indeed very glad that our multi-spectroscopic approach is also applicable to any other research on metal nanocrystals. That’s why this study contributes to an emerging research area on metal nanocrystals in a broader context,” says Dr. Christoph Hennig. “And the HZDR’s own measuring station at the ESRF provides the best possible opportunities for this research area of metal nanocrystals which directly contributes to industrial applications.”

A. Ikeda-Ohno et al., Chem. Eur. J., 19(23), 7348-7360 (2013), DOI: 10.1002/chem.201204101.

Further Information:
Dr. Atsushi Ikeda-Ohno
School of Civil and Environmental Engineering
The University of New South Wales
UNSW, Sydney, New South Wales 2052, Australia
Phone: +61 2 9385 0128

Dr. Christoph Hennig | Dr. Vinzenz Brendler
Institute of Ressource Ecology at HZDR
Rossendorf Beamline at the ESRF/Grenoble
Phone: +33 476 88 - 2005 | +49 351 260 - 3210 |

Media Contact:
Dr. Christine Bohnet
Press Officer
Phone: +49 351-260 2450 or +49 160 969 288 56 | |
Helmholtz-Zentrum Dresden-Rossendorf | Bautzner Landstr. 400 | 01328 Dresden | Germany

The Helmholtz-Zentrum Dresden-Rossendorf (HZDR) conducts research in the sectors energy, health, and matter. It focuses its research on the following topics:

• How can energy and resources be used efficiently, safely, and sustainably?
• How can malignant tumors be visualized and characterized more precisely and treated effectively?
• How do matter and materials behave in strong fields and at the smallest dimensions?

To answer these scientific questions, five large-scale research facilities provide unique research opportunities. These facilities are also accessible to external users.

The HZDR has been a member of the Helmholtz Association, Germany’s largest research organization, since 2011. It has four locations in Dresden, Leipzig, Freiberg, and Grenoble and employs about 1,000 people – approx. 450 of whom are scientists including 160 doctoral candidates.

Dr. Christine Bohnet | Helmholtz-Zentrum
Further information:

More articles from Materials Sciences:

nachricht From ancient fossils to future cars
21.10.2016 | University of California - Riverside

nachricht Study explains strength gap between graphene, carbon fiber
20.10.2016 | Rice University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>