Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers synthesize atomically precise diamond-shaped nanoclusters of silver

12.09.2016

A wide international collaboration involving researchers from four countries - China, Australia, Germany and Finland - have managed to synthesize and characterize two previously unknown, record-large silver nanoclusters of 136 and 374 silver atoms.

These diamond-shaped nanoclusters (see Figure), consisting of a silver core of 2 to 3 nanometers and a protecting layer of silver atoms and organic thiol molecules, are the largest ones whose structure is now known to atomic precision. The research (1) was published in Nature Communications on 9 September 2016.


This figure shows: Upper row: (a) top and (b) side view of the 136-atom silver nanocluster. Lower row: (c) top and (d) side view of the 374-atom silver nanocluster. The metal cores of these clusters have a diameter of 2 and 3 nm, respectively. Silver atoms in the metal core are denoted by large orange sphere. The core is protected by a silver-thiol layer (green: silver; yellow: sulfur; carbon: gray). Courtesy of Nanfeng Zheng, Xiamen University.

Credit: The University of Jyväskylä

The nanoclusters where synthesized in Xiamen University in China and characterized by X-ray crystallography and electron microscopy in China, Australia and Germany. Their electronic structure and optical properties were studied computationally in the Nanoscience Center (NSC) of the University of Jyväskylä in Finland.

Gold nanoclusters that are stabilized by a thiol molecular layer have been known for decades, but only during the latest years silver clusters have attracted more interest in the research community. Silver is a desirable material for nanocluster synthesis since it is a cheaper metal than gold and its optical properties are better controllable for applications. However, synthesis recipes that would produce silver clusters that are stable for prolonged times are not so widely known as for gold.

"These largest atomically precise silver nanoclusters known thus far serve as excellent model systems to understand how silver nanoparticles grow," says Professor Nanfeng Zheng whose research group prepared the clusters in Xiamen University in China. "The internal structure of the metal core is a combination of little crystallites of silver that are joined together to form a five-fold symmetric diamond-shape structure."

"From a theoretical point of view these new clusters are very interesting," says Academy Professor Hannu Häkkinen from the NSC in Jyväskylä. "These clusters are already big enough that they have properties similar to silver metal, such as strong absorption of light leading to collective oscillations of the electron cloud known as plasmons, yet small enough that we can study their electronic structure in detail. Much to our surprise, the calculations showed that electrons in the organic molecular layer take part actively in the collective oscillation of the silver electrons. It seems possible to then activate these clusters by light in order to do chemistry at the ligand surface."

###

The other NSC researchers involved in the work were Xi Chen and Lauri Lehtovaara. The computational work was done at the CSC - the Finnish IT Centre for Science. The work at the University of Jyväskylä was supported by the Academy of Finland.

More information:

Academy Professor Hannu Häkkinen, University of Jyväskylä, Finland, hannu.j.hakkinen(at)jyu.fi tel:+358 400 247 973

Professor Nanfeng Zheng, Xiamen University, China, nfzheng(at)xmu.edu.cn

Academy of Finland Communications
Communications Specialist Leena Vähäkylä
tel. +358 295 335 139
firstname.lastname(at)aka.fi

References:

(1) H. Yang, Y. Wang, X. Chen, X. Zhao, L. Gu, H. Huang, J. Yan, C. Xu, G. Li, J. Wu, A.J. Edwards, B. Dittrich, Z. Tang, D. Wang, L. Lehtovaara, H. Häkkinen and N. Zheng, "Plasmonic twinned silver nanoparticles with molecular precision", Nature Communications 7, 12809 (2016), published online 9 September 2016, doi: 10.1038/ncomms12809

Figure: Upper row: (a) top and (b) side view of the 136-atom silver nanocluster. Lower row: (c) top and (d) side view of the 374-atom silver nanocluster. The metal cores of these clusters have a diameter of 2 and 3 nm, respectively. Silver atoms in the metal core are denoted by large orange sphere. The core is protected by a silver-thiol layer (green: silver; yellow: sulfur; carbon: gray). Courtesy of Nanfeng Zheng, Xiamen University.

Hannu Häkkinen | EurekAlert!

More articles from Physics and Astronomy:

nachricht Studying fundamental particles in materials
17.01.2017 | Max-Planck-Institut für Struktur und Dynamik der Materie

nachricht Seeing the quantum future... literally
16.01.2017 | University of Sydney

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: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>