13-Nov-2020 - Friedrich-Alexander-Universität Erlangen-Nürnberg

Carbyne – an unusual form of carbon

International team of researchers investigates optical band gap of carbon compound

Which photophysical properties does carbyne have? This was the subject of research carried out by scientists at FAU, the University of Alberta, Canada, and the Ecole Polytechnique Fédérale de Lausanne in Switzerland, which has led to a greater understanding of the properties of this unusual form of carbon.

‘Carbon has a very special status in the periodic table of the elements and forms the basis for all forms of life due to the extremely large number of chemical compounds it can form,’ explains Prof. Dr. Dirk M. Guldi at the Chair of Physical Chemistry I at FAU. ‘The most well-known examples are three-dimensional graphite and diamond. However, two-dimensional graphene, one-dimensional nanotubes and zero-dimensional nanodots also open up new opportunities for electronics applications in the future.’

Material with extraordinary properties

Carbyne is a modification of carbon, known as an allotrope. It is manufactured synthetically, comprises one single and very long chain of carbon atoms, and is regarded as a material with extremely interesting electronic and mechanical properties. ‘However, carbon has a high level of reactivity in this form,’ emphasises Prof. Dr. Clémence Corminboef from EPFL. ‘Such long chains are extremely unstable and thus very difficult to characterise.’

Despite this fact, the international research team successfully characterised the chains using a roundabout route. The scientists led by Prof. Dr. Dirk M. Guldi at FAU, Prof. Dr. Clémence Corminboeuf, Prof. Dr. Holger Frauenrath from EPFL and Prof. Dr. Rik R. Tykwinski from the University of Alberta questioned existing assumptions about the photophysical properties of carbyne and gained new insights.

During their research, the team mainly focused on what are known as oligoynes. ‘We can manufacture carbyne chains of specific lengths and protect them from decomposition by adding a type of bumper made of atoms to the ends of the chains. This class of compound has sufficient chemical stability and is known as an oligoyne,’ explains Prof. Dr. Holger Frauenrath from EPFL.

Using the optical band gap

The researchers specifically manufactured two series of oligoynes with varying symmetries and with up to 24 alternating triple and single bonds. Using spectroscopy, they subsequently tracked the deactivation processes of the relevant molecules from excitation with light up to complete relaxation. ‘We were thus able to determine the mechanism behind the entire deactivation process of the oligoynes from an excited state right back to their original initial state and, thanks to the data we gained, we were able to make a prediction about the properties of carbyne,’ concludes Prof. Dr. Rik R. Tykwinski from the University of Alberta.

One important finding was the fact that the so-called optical band gap is actually much smaller than previously assumed. Band gap is a term from the field of semiconductor physics and describes the electrical conductivity of crystals, metals and semiconductors. ‘This is an enormous advantage,’ says Prof. Guldi. ‘The smaller the band gap, the less energy is required to conduct electricity.’ Silicon, for example, which is used in microchips and solar cells, possesses this important property. Carbyne could be used in conjunction with silicon in the future due to its excellent photophysical properties.

Friedrich-Alexander-Universität Erlangen-Nürnberg

Recommend news PDF version / Print

Share on

Facts, background information, dossiers
  • carbyne
  • carbon
  • band gap
More about Friedrich-Alexander-Universität Erlangen-Nürnberg
  • News

    Nano-Rust: Smart Additive for Autonomous Temperature Control

    The right temperature matters – whether in technical processes, for the quality of food and medicines, or the lifetime of electronic components and batteries. For this purpose, temperature indicators record (un)desired temperature increases that can be read out later. Researchers in the gro ... more

    Green hydrogen glows pink

    Researchers at the Department of Chemistry and Pharmacy and the Chair of Thermal Process Technology at FAU have succeeded in making invisible hydrogen gas visible to the naked eye in order to prevent the risk of fires and explosions. The key to their research is what is known as suprapartic ... more

    Attosecond camera for nanostructures

    Physicists of the Laboratory for Attosecond Physics at the Max Planck Institute of Quantum Optics and the Ludwig-Maximilians-Universität Munich in collaboration with scientists from the Friedrich-Alexander-Universität Erlangen-Nürnberg have observed a light-matter phenomenon in nano-optics, ... more

More about University of Alberta
  • News

    The Secret Contamination of Polar Bears

    Using a new approach to measure chemical contaminants in polar bears, scientists from Canada and the United States found a large variety of new chlorinated and fluorinated substances, including many new polychlorinated biphenyl metabolites. Worryingly, these previously unrecognized contamin ... more

    Next generation of neuroscience tools

    UAlberta chemistry professor Robert Campbell is developing new ways to see and manipulate the activity of neurons in the brain, which could revolutionize the way we understand the organ that controls most of the activities of the body. "We want to help other researchers apply these new neur ... more

    New window into the nanoworld

    For the first time ever, scientists have captured images of terahertz electron dynamics of a semiconductor surface on the atomic scale. The successful experiment indicates a bright future for the new and quickly growing sub-field called terahertz scanning tunneling microscopy (THz-STM), pio ... more

More about Ecole Polytechnique Fédérale de Lausanne
  • News

    Monitoring gene activities in living cells

    Researchers from ETH Zurich and EPFL are expanding the emerging field of single-​cell analysis with a ground-​breaking method: Live-​seq makes it possible to measure the activity of thousands of genes in a single cell without having to isolate and destroy it. Modern biology is increasingly ... more

    Tracking chirality in real time

    Scientists at EPFL have developed a new laser-based technique that can measure ultrafast changes in the structural symmetry of molecules, called chirality, tracking their conformational shifts in real time. In a collaboration with researchers from the Universities of Geneva and Pisa, the br ... more

    Molecular device turns infrared into visible light

    Light is an electromagnetic wave: it consists of oscillating electric and magnetic fields propagating through space. Every wave is characterized by its frequency, which refers to the number of oscillations per second, measured in Hertz (Hz). Our eyes can detect frequencies between 400 and 7 ... more

  • Videos

    The Gates of Serotonin

    EPFL scientists have elucidated for the first time how a notoriously elusive serotonin receptor functions with atom-level detail. The receptor transmits electrical signals in neurons and is involved in various disorders, meaning that the discovery opens the way for new treatments. The recep ... more