The increasing demand for smaller and faster semiconductor technology intensifies the search for ‘next-generation’ materials that work well at the nanoscale as alternatives to silicon, which many regard as having reached its limit.
One such material is graphene, and now a new approach that successfully produces long, flat, nanoscale ‘ribbons’ of this type of carbon, brings closer its use as a semiconductor in computers, phones, and other electronic technologies.
The new approach was developed by scientists at the Max Planck Institute for Polymer Research in Mainz, Germany, working with teams from other European establishments, including the University of Manchester in the UK.
They reported their work, “Synthesis of structurally well-defined and liquid-phase-processable graphene nanoribbons” , in a recent issue of the journal Nature Chemistry.
Graphene is a one-atom-thick structure – it is the strongest, thinnest and lightest material on Earth.
Graphene is an attractive material for use in nanoscale electronics
Graphene is attracting interest as a material suitable for use in nanoscale electronics not only because it is a single-atom-thick carbon crystal, but because it has some very useful, unique properties, such as its ability to allow electrons and other charge carriers to move through it easily at high speed.
However, there are some significant challenges to overcome before graphene is anywhere near ready for use as a semiconductor. One of these is how to manufacture it in the sizes and shapes that would be required.
Challenge is to make structurally well-defined graphene nanoribbons
One idea that has been suggested is to try and make long, structurally well-defined graphene nanoribbons (GNRs). However, the ability to fabricate what the researchers call ‘processable and longitudinally well-extended GNRs,’ suitable for use in electronics, is a major challenge.
In this new study, the scientists used a ‘molecule toolbox’ to make ‘unprecedented longitudinal extensions of GNRs’ while preserving their high structural definition.
And the team at Manchester University, led by Dr Cinzia Casiraghi, used a range of techniques – including Raman spectroscopy – to confirm that the GNRs were structurally well-defined and had excellent charge-carrier mobility.
Raman spectroscopy expected to play a key role in confirming properties of graphene nanoribbons
The researchers are hopeful that their new approach will lead the way to successful production of a form of graphene that can be used in a range of electronic components, as Dr Casiraghi explains:
“The GNRs produced with this method can allow development of graphene-based transistors, but they can also be used as active material in solar cells, chemical sensors and as novel energy storage material.”
“Because of the potential uses of this material, Raman spectroscopy is expected to play a crucial role in determining the optical and electronic properties of the ribbons.”
Last month, Market Business News reported how a team of British, Chinese and Belgian scientists working in the new field of ‘nanophotonics’, developed a new way of improving the efficiency of solar cells.