Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

All wired up: New molecular wires for single-molecule electronic devices

28.08.2018

Scientists at Tokyo Institute of Technology designed a new type of molecular wire doped with organometallic ruthenium to achieve unprecedentedly higher conductance than earlier molecular wires. The origin of high conductance in these wires is fundamentally different from similar molecular devices and suggests a potential strategy for developing highly conducting "doped" molecular wires.

Since their conception, researchers have tried to shrink electronic devices to unprecedented sizes, even to the point of fabricating them from a few molecules.


The proposed wire is 'doped' with a ruthenium unit that enhances its conductance to unprecedented levels compared with previously reported similar molecular wires.

Credit: Journal of the American Chemical Society

Molecular wires are one of the building blocks of such minuscule contraptions, and many researchers have been developing strategies to synthesize highly conductive, stable wires from carefully designed molecules.

A team of researchers from Tokyo Institute of Technology, including Yuya Tanaka, designed a novel molecular wire in the form of a metal electrode-molecule-metal electrode (MMM) junction including a polyyne, an organic chain-like molecule, "doped" with a ruthenium-based unit Ru(dppe)2.

The proposed design, featured in the cover of the Journal of the American Chemical Society, is based on engineering the energy levels of the conducting orbitals of the atoms of the wire, considering the characteristics of gold electrodes.

Using scanning tunneling microscopy, the team confirmed that the conductance of these molecular wires was equal to or higher than those of previously reported organic molecular wires, including similar wires "doped" with iron units. Motivated by these results, the researchers then went on to investigate the origin of the proposed wire's superior conductance.

They found that the observed conducting properties were fundamentally different from previously reported similar MMM junctions and were derived from orbital splitting. In other words, orbital splitting induces changes in the original electron orbitals of the atoms to define a new "hybrid" orbital facilitating electron transfer between the metal electrodes and the wire molecules. According to Tanaka, "such orbital splitting behavior has rarely been reported for any other MMM junction".

Since a narrow gap between the highest (HOMO) and lowest (LUMO) occupied molecular orbitals is a crucial factor for enhancing conductance of molecular wires, the proposed synthesis protocol adopts a new technique to exploit this knowledge, as Tanaka adds "The present study reveals a new strategy to realize molecular wires with an extremely narrow HOMO?LUMO gap via MMM junction formation."

This explanation for the fundamentally different conducting properties of the proposed wires facilitate the strategic development of novel molecular components, which could be the building blocks of future minuscule electronic devices.

Media Contact

Emiko Kawaguchi
media@jim.titech.ac.jp
81-357-342-975

http://www.titech.ac.jp/english/index.html 

Emiko Kawaguchi | EurekAlert!
Further information:
https://www.titech.ac.jp/english/news/2018/042199.html
http://dx.doi.org/10.1021/jacs.8b04484

More articles from Materials Sciences:

nachricht World's first passive anti-frosting surface fights ice with ice
18.09.2018 | Virginia Tech

nachricht A novel approach of improving battery performance
18.09.2018 | Ulsan National Institute of Science and Technology (UNIST)

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists present new observations to understand the phase transition in quantum chromodynamics

The building blocks of matter in our universe were formed in the first 10 microseconds of its existence, according to the currently accepted scientific picture. After the Big Bang about 13.7 billion years ago, matter consisted mainly of quarks and gluons, two types of elementary particles whose interactions are governed by quantum chromodynamics (QCD), the theory of strong interaction. In the early universe, these particles moved (nearly) freely in a quark-gluon plasma.

This is a joint press release of University Muenster and Heidelberg as well as the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt.

Then, in a phase transition, they combined and formed hadrons, among them the building blocks of atomic nuclei, protons and neutrons. In the current issue of...

Im Focus: Patented nanostructure for solar cells: Rough optics, smooth surface

Thin-film solar cells made of crystalline silicon are inexpensive and achieve efficiencies of a good 14 percent. However, they could do even better if their shiny surfaces reflected less light. A team led by Prof. Christiane Becker from the Helmholtz-Zentrum Berlin (HZB) has now patented a sophisticated new solution to this problem.

"It is not enough simply to bring more light into the cell," says Christiane Becker. Such surface structures can even ultimately reduce the efficiency by...

Im Focus: New soft coral species discovered in Panama

A study in the journal Bulletin of Marine Science describes a new, blood-red species of octocoral found in Panama. The species in the genus Thesea was discovered in the threatened low-light reef environment on Hannibal Bank, 60 kilometers off mainland Pacific Panama, by researchers at the Smithsonian Tropical Research Institute in Panama (STRI) and the Centro de Investigación en Ciencias del Mar y Limnología (CIMAR) at the University of Costa Rica.

Scientists established the new species, Thesea dalioi, by comparing its physical traits, such as branch thickness and the bright red colony color, with the...

Im Focus: New devices based on rust could reduce excess heat in computers

Physicists explore long-distance information transmission in antiferromagnetic iron oxide

Scientists have succeeded in observing the first long-distance transfer of information in a magnetic group of materials known as antiferromagnets.

Im Focus: Finding Nemo's genes

An international team of researchers has mapped Nemo's genome

An international team of researchers has mapped Nemo's genome, providing the research community with an invaluable resource to decode the response of fish to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

One of the world’s most prominent strategic forums for global health held in Berlin in October 2018

03.09.2018 | Event News

4th Intelligent Materials - European Symposium on Intelligent Materials

27.08.2018 | Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

 
Latest News

Glacial engineering could limit sea-level rise, if we get our emissions under control

20.09.2018 | Earth Sciences

Warning against hubris in CO2 removal

20.09.2018 | Earth Sciences

Halfway mark for NOEMA, the super-telescope under construction

20.09.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>