Professor Jonathan Coleman, Principal Investigator at CRANN and the School of Physics. Credit: Trinity College Dublin. |
A new way of splitting layered materials to give atom thin “nanosheets” has
been discovered. This has led to a range of novel two-dimensional nanomaterials
with chemical and electronic properties that have the potential to enable new
electronic and energy storage technologies. The collaborative international
research led by the Centre for Research on Adaptive Nanostructures and
Nanodevices (CRANN), Trinity College Dublin, Ireland, and the Univ. of Oxford
has been published in Science.
The research has been funded by Science Foundation Ireland.
The scientists have invented a versatile method for creating these atom
thin nanosheets from a range of materials using common solvents and ultrasound,
utilising devices similar to those used to clean jewellery. The new method is
simple, fast, and inexpensive, and could be scaled up to work on an industrial
scale.
“Of the many possible applications of these new nanosheets, perhaps the
most important are as thermoelectric materials. These materials, when
fabricated into devices, can generate electricity from waste heat. For example,
in gas-fired power plants approximately 50% of energy produced is lost as waste
heat, while for coal and oil plants the figure is up to 70%. However, the
development of efficient thermoelectric devices would allow some of this waste
heat to be recycled cheaply and easily, something that has been beyond us, up
until now,” explained Professor Jonathan Coleman, Principal Investigator at
CRANN and the School of Physics, Trinity College Dublin who led the research
along with Dr Valeria Nicolosi in the Department of Materials at the Univ. of
Oxford.
This research can be compared to the work regarding the two-dimensional
material graphene, which won the Nobel Prize in 2010. Graphene has generated
significant interest because when separated into individual flakes, it has
exceptional electronic and mechanical properties that are very different to
those of its parent crystal, graphite. However, graphite is just one of
hundreds of layered materials, some of which may enable powerful new
technologies.
Coleman’s work will open up over 150 similarly exotic layered materials—such
as boron nitride, molybdenum disulfide, and Bismuth telluride—that have the potential
to be metallic, semiconducting, or insulating, depending on their chemical
composition and how their atoms are arranged. This new family of materials
opens a whole range of new “super” materials.
For decades researchers have tried to create nanosheets from layered
materials in order to unlock their unusual electronic and thermoelectric
properties. However, previous methods were time consuming, laborious, or of
very low yield, and so unsuited to most applications.
“Our new method offers low-costs, a very high yield and a very large
throughput: within a couple of hours, and with just 1 mg of material, billions
and billions of one-atom-thick nanosheets can be made at the same time from a
wide variety of exotic layered materials,” explained Dr Nicolosi, from the
Univ. of Oxford.
These new materials are also suited for use in next generation batteries—“supercapacitors”—which
can deliver energy thousands of times faster than standard batteries, enabling
new applications such as electric cars. Many of these new atomic layered
materials are very strong and can be added to plastics to produce super-strong
composites. These will be useful in a range of industries from simple
structural plastics to aeronautics.
