Using Single Molecules to Conduct Electricity

A multinational team of researchers have made progress in using single molecule wires as electric conductors. Image courtesy of TU Graz

From the wire. A team of multinational researchers have reported success in using single-molecule wires to conduct electricity between two metal electrodes. According to an abstract on the research, the research paves the way for the development of novel molecular components envisioned as functional units in nanoscale devices.

In the past, one of the central challenges of using single molecules to conduct electricity is that most molecules only start to conduct once a large voltage has been applied. An international research team comprising scientists from the Graz University of Technology, Humboldt University in Berlin,  MIT,  Montan University in Leoben and Georgia Institute of Technology has shown that molecules containing an odd number of electrons are much more conductive at low bias voltages. These fundamental findings in the highly dynamic research field of nanotechnology open up a diverse array of possible applications including more-efficient microchips and components with considerably increased storage densities.

Most stable molecules have a closed shell configuration with an even number of electrons. Molecules with an odd number of electrons tend to be harder for chemists to synthesise but they conduct much better at low bias voltages. Although using an odd rather than an even number of electrons may seem simple, it is a fundamental realisation in the field of nanotechnology – because as a result of this, metal elements in molecular electronic circuits can now be replaced by single molecules. “This brings us a considerable step closer to the ultimate minitiurisation of electronic components,” explains Egbert Zojer from the Institute for Solid State Physics of the Graz University of Technology.

The motivation for this basic research is the vision of circuits that only consist of a few molecules. “If it is possible to get molecular components to completely assume the functions of a circuit’s various elements, this would open up a wide array of possible applications, the full potential of which will only become apparent over time. In our work we show a path to realising the highly electrically conductive elements,” Zojer reports the momentous consequences of the discovery.

Specific new perspectives are opened up in the field of molecular electronics, sensor technology or the development of bio-compatible interfaces between inorganic and organic materials: The latter refers to the contact with biological systems such as human cells, for instance, which can be connected to electronic circuits in a biocompatible fashion via the conductive molecules.

More information is available on the research from Science Daily.

Tags: electrical conductivity, electrodes, Georgia Institute of Technology, Graz University of Technology, Humboldt University in Berlin, MIT, molecules, Montan University in Leoben