Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Organic computers are coming

15.07.2016

Scientists found a molecule that will help to make organic electronic devices

A team of the Lomonosov MSU researchers in collaboration with their German colleagues from the Institute of Polymer Research in Dresden (Leibniz Institute) managed to find a molecule that, to their opinion, could give the impetus to the development of organic electronics. The results of the work were published in Advanced Materials.


The energy levels of the studied systems and a synchrotron X-ray diffractogram measured on a thin film of an organic semiconductor doped with a derivative of [3]-radialene.

Credit: The Lomonosov Moscow Stte University

Scientists from the Moscow State University together with colleagues from Germany have found that a derivative of [3]-radialene, a molecule known to the science for nearly 30 years, can be used to create organic semiconductors. Dmitry Ivanov, the Head of the Laboratory of Materials Engineering at the Department of Fundamental Physics and Chemical Engineering, Moscow State University, believes that the achievement will greatly contribute to the development of organic electronics and, in particular, to fabrication of organic light emitting diodes and new classes of organic solar cells.

Organic or "plastic" electronics is a relatively young scientific field, which came to life about 15-20 years ago. Its purpose is the development of electronic devices based on organic materials. This type of devices is yet inferior to the standard silicon-based electronics in terms of performance, and also less durable. But it also has advantages -- lightness, thinness, flexibility, transparency, and most importantly -- plastic electronics is much cheaper than silicon. The main applications of organic electronics include solar cells, which will be much cheaper than the silicon-based modules (high cost is one of the reasons, which restricts the latter from covering large areas and thus make better use of the sun energy). Also, organic electronics can be used to design organic light emitting devices and field-effect transistors.

The molecule in question is the so-called dopant, whose addition to a semiconducting polymer substantially increases its electrical conductivity. The dopants for inorganic semiconductors are widely used already for decades, however, according to one of the article's co-authors, Dmitry Ivanov, for organic conductors this field is far less studied. Currently, the most commonly used are fluorinated dopants. In combination with different organic semiconductors they are able to dramatically increase their electrical conductivity, but not all polymers that are used today in the "plastic" electronics are suitable.

'Together with our Drezden colleagues we decided to design a completely new type of low molecular weight dopant for the organic semiconductor,' says Dmitry Ivanov. 'And here it was important to choose a molecule that it was not only suitable in its energy levels, but, importantly, the dopant must be well mixed with the polymer, so that in contact with the polymer it does not segregate in a separate phase, eventually crystallizing and, in fact, losing contact with the polymer'.

The main contribution of Ivanov's laboratory in this work consisted in exploring the physics of the phase transitions, physics of mixing in such binary systems, in the other words -- in finding a suitable candidate in terms of polymer physics.

And such a candidate was found. It happened to be a derivative of [3]-radialene. This is a small planar molecule in which the carbon atoms are connected to form a triangular structure. Among other potentially interesting compounds, [3]-radialene has the most energetically suitable LUMO level, i.e. the lowest unoccupied molecular orbital. This means that with its help the electrons are easily extracted from the semiconducting polymer matrix, becoming free charges and thereby increasing the conductivity of the doped material. [3]-Radialene thus becomes the strongest dopant for the organic semiconductor among those that are known in the scientific literature.

The experiments with the [3]-radialene, also confirmed by the results of quantum-chemical calculations, show that the substance is well mixed with a semiconducting polymer and allows to increase the electrical conductivity of the polymer by several tens and even hundreds of times. It has been found that up to 50 percent of the dopant's content in the polymer the phase separation does not occur, but the crystalline structure of the polymer is gradually changed. This meant that the dopant molecules are included in the polymer crystalline lattice and form the so-called co-crystal. And the formation of co-crystals, according to Ivanov, is precisely one of the main reasons for the high efficiency of the new compound.

The described new dopant, as well its fluorinated and currently the most popular analogues, belongs to the category of electron-deficient organic dopants, Dmitry Ivanov tells. 'Fluorine substituents are known to strongly pull the electrons away from the central part of the molecule, which increases the whole conductivity of the doped polymer. In the present work, the chemical structure of the dopant is completely different, and, in fact, appears to be even better. Perfect mixing of our dopant with the polymer matrix is, I think, the key to its performance. This could pave the way to fabrication of new organic solar cells with improved characteristics. We also think about production of organic field-effect transistors. I think it will give a significant boost to the development of organic electronic devices.'

Media Contact

Vladimir Koryagin
science-release@rector.msu.ru

http://www.msu.ru 

Vladimir Koryagin | EurekAlert!

More articles from Information Technology:

nachricht Smart Computers
21.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht AI implications: Engineer's model lays groundwork for machine-learning device
18.08.2017 | Washington University in St. Louis

All articles from Information Technology >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

Cholesterol-lowering drugs may fight infectious disease

22.08.2017 | Health and Medicine

Meter-sized single-crystal graphene growth becomes possible

22.08.2017 | Materials Sciences

Repairing damaged hearts with self-healing heart cells

22.08.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>