Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists discover 'electron equivalents' in colloidal systems

28.08.2019

Scientists find unusual behaviors in colloidal crystals.

Atoms have a positively charged center surrounded by a cloud of negatively charged particles. This type of arrangement, it turns out, can also occur at a more macroscopic level, giving new insights into the nature of how materials form and interact.


Argonne scientists have used small particles as electron equivalents to create metallic behavior in colloidal systems primarily composed of larger particles. These small particles could act as messengers, carrying information or other molecules over distances.

Credit: Byeongdu Lee / Argonne National Laboratory

In a new study from the U.S. Department of Energy's (DOE) Argonne National Laboratory, scientists have examined the internal structure of a material called a colloidal crystal, which consists of a highly ordered array of larger and smaller particles interspersed in regular arrangements. A greater knowledge of how colloidal crystals are structured and behave could help scientists determine the applications to which they are best suited, like photonics.

"The smaller particles essentially act like a glue that holds the larger particle arrangement together," -- Byeongdu Lee, Argonne X-ray physicist.

... more about:
»DNA »Photonics »X-ray »colloidal crystal »nanometers

In pioneering research outlined in a recent issue of Science, scientists tethered smaller particles to larger ones using DNA, allowing them to determine how the smaller particles filled in the regions surrounding the larger ones. When using particles as small as 1.4 nanometers -- extremely small for colloidal particles -- scientists observed an exciting effect: The small particles roamed around regularly ordered larger particles instead of remaining locked in an ordered fashion.

Because of this behavior, the colloidal crystals could be designed to lead to a variety of new technologies in the field of optics, catalysis, and drug delivery. The small particles have the potential to act as messengers, carrying other molecules, electric current or information from one end of a crystal to another.

"The smaller particles essentially act like a glue that holds the larger particle arrangement together," said Argonne X-ray physicist and study author Byeongdu Lee. "With only a few beads of glue, the best position to place them is on the corners between the larger particles. If you add more glue beads, they would overflow to the edges."

The small particles that sit on the corners tend to stay still -- a configuration Lee called localization. The additional particles that are on the edges have more freedom of movement, becoming delocalized. By being tethered to larger particles and with the ability to be both localized and delocalized, the small particles act as "electron equivalents" in the crystal structure. The delocalization of small particles, which the authors called metallicity, had not been observed so far in colloidal particle assemblies.

Additionally, since the small particles delocalize in part, the effect creates a material that challenges most traditional definitions of a crystal, according to Lee.

"Normally, when you change the composition of a crystal, the structure changes as well," he said. "Here, you can have a material that is able to maintain its overall structure with different proportions of its components."

To image the structure of the colloidal crystals, Lee and his colleagues used the high-brightness X-ray beams provided by Argonne's Advanced Photon Source (APS), a DOE Office of Science User Facility. The APS offered a key advantage in that it allowed the scientists to observe the structure of the crystal directly in solution. "This system is only stable in solution, once it dries, the structure deforms," Lee said.

###

A paper based on the study, "Particle analogs of electrons in colloidal crystals," appeared in the June 21 issue of Science.  Other authors on the study included Martin Girard, Shunzhi Wang, Jingshan Du, Anindita Das, Ziyin Huang, Vinayak Dravid, Chad Mirkin and Monica Olvera de la Cruz, all of Northwestern University.

The Argonne research was funded by DOE's Office of Science (Office of Basic Energy Sciences).

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

The U.S. Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://energy.gov/science.

Media Contact

Beth Schlesinger
bschlesinger@anl.gov
630-252-5325

 @argonne

http://www.anl.gov 

Beth Schlesinger | EurekAlert!
Further information:
https://www.anl.gov/article/scientists-discover-electron-equivalents-in-colloidal-systems
http://dx.doi.org/10.1126/science.aaw8237

Further reports about: DNA Photonics X-ray colloidal crystal nanometers

More articles from Physics and Astronomy:

nachricht UMD-led study captures six galaxies undergoing sudden, dramatic transitions
19.09.2019 | University of Maryland

nachricht Stevens team closes in on 'holy grail' of room temperature quantum computing chips
19.09.2019 | Stevens Institute of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Stevens team closes in on 'holy grail' of room temperature quantum computing chips

Photons interact on chip-based system with unprecedented efficiency

To process information, photons must interact. However, these tiny packets of light want nothing to do with each other, each passing by without altering the...

Im Focus: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

Im Focus: The working of a molecular string phone

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.

This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

AI for Laser Technology Conference: optimizing the use of lasers with artificial intelligence

29.08.2019 | Event News

 
Latest News

UMD-led study captures six galaxies undergoing sudden, dramatic transitions

19.09.2019 | Physics and Astronomy

Study points to new drug target in fight against cancer

19.09.2019 | Health and Medicine

New tool improves beekeepers' overwintering odds and bottom line

19.09.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>