Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers from Saarbruecken arrange nanoparticles like "giant atoms"

18.06.2012
Scientists at INM – Leibniz Institute for New Materials found out that certain nanoparticles assemble into groups as if they were atoms. Like the atoms of metals or noble gases, they form specific structures depending on their number.
Through their findings, the researchers are now able to make precisely defined structures from nanoparticles. Normally, nanoparticles form rather disordered, often loose and fuzzy clusters. The results were recently published in the scientific magazine "Nano Letters".

The researchers assume that this unexpected behavior derives from the smallness of the nanoparticles. "We assume that the nanoparticles with a core diameter of only six nanometers show a behavior similar to atoms: They move very fast, collide with each other and attract each other", explains Tobias Kraus, head of the Structure Formation Group. Therefore, they can assemble almost as orderly as atoms.
Depending on the number of nanoparticles, the scientists can now predict which three-dimensional lattice are formed by the particles. "Imagine that clusters with 20 particles look like a sphere, whereas 40 particles arrange rather like a cube and 60 particles form a pyramid", explains Kraus, who holds degrees in materials science and chemical engineering. It is possible to produce specific shapes by defining the quantity of the nanoparticles in the production process. "Since nanoparticles arranged as a sphere have different properties than nanoparticles arranged as a cube, we can influence properties by the number of the particles", says Kraus. "A rather elongated cluster may not fit through the pores of a filter, for example, although it contains more particles than a spherical cluster."

The scientists use a well-established principle to force the nanoparticles into this highly ordered structure. To begin with, all gold nanoparticles must be of the same size, which is achieved in a classic preparation procedure: The researchers dissolve little bars of gold in a concentrated acid, combine the dissolved gold with organic molecules and add surface-active substances. When heating this mixture, the scientists obtain nanoparticles with a diameter of six millionths of a millimeter. The nanoparticles swim in oil, which is then dispersed into droplets. Each droplet contains several nanoparticles. "As these droplets evaporate, the space for the nanoparticles is increasingly reduced so that they assemble in an orderly manner and form the ordered clusters", says Kraus.

In the future, the group will integrate various particles into the clusters, each of them having a different task. This may be a first step to building microscopic machinery from particles.
Original publication: Johann Lacava, Philip Born, Tobias, Kraus, "Nanoparticle Clusters with Lennard-Jones Geometries", Nano Letters, DOI: 10.1021/nl3013659

Contact:
Dr. Tobias Kraus
Structure Formation Group
INM – Leibniz Institute for New Materials
Phone: +49 681 9300 389
Email: tobias.kraus@inm-gmbh.de

INM is focused on the research and development of materials – for today, tomorrow and the future. Chemists, physicists, biologists, materials and engineering scientists shape the work at INM. From molecule to pilot production, they follow the recurring questions: Which material properties are new, how can they be investigated and how can they be used in the future?

INM – Leibniz Institute for New Materials, situated in Saarbruecken/Germany, is an internationally leading centre for materials research. It is a scientific partner to national and international institutes and a provider of research and development for companies throughout the world. INM is an institute of the Scientific Association Gottfried Wilhelm Leibniz and employs around 180 collaborators. Its main research fields are Chemical Nanotechnology, Interface Materials, and Materials in Biology.

Dr. Carola Jung | idw
Further information:
http://www.inm-gmbh.de/
http://www.wgl.de/

More articles from Materials Sciences:

nachricht New biomaterial could replace plastic laminates, greatly reduce pollution
21.09.2017 | Penn State

nachricht Stopping problem ice -- by cracking it
21.09.2017 | Norwegian University of Science and Technology

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Fraunhofer ISE Pushes World Record for Multicrystalline Silicon Solar Cells to 22.3 Percent

25.09.2017 | Power and Electrical Engineering

Usher syndrome: Gene therapy restores hearing and balance

25.09.2017 | Health and Medicine

An international team of physicists a coherent amplification effect in laser excited dielectrics

25.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>