graphene has proven to be a nano-material with several
desirable properties in the technology sphere, it is yet to
find a killer application that will pull it firmly
laboratories and into mainstream commercialisation.
This was the overarching sentiment of speakers during the
first day of Graphene Live! 2014, which is taking place this
week in Berlin, Germany.
Graphene is a two-dimensional, crystalline allotrope of
carbon produced from either natural graphite, using an
exfoliation route or synthetically, through processes such as
chemical vapour deposition (CVD).
hit the headlines over the past few years due to its
exceptional properties, which include high intrinsic
conductivity, high specific surface area, ultra thinness (one
atom thick) and an inert basal surface.
These characteristics have granted graphene research and
development airtime around the world, especially in relation to
its potential use in energy storage and consumer
graphene exhibits properties that make it possible to
improve the performance of technologies such as
supercapacitors, batteries and solar cells, it has not yet
found an application that will pull it firmly out of research
and development, according to Dr Khasha Ghaffarzadeh, head of
consulting at IDTechEx.
Graphene clearly has
significant potential, he said, adding that
there is not yet a killer application [for
Ivan Buckley, project manager at the UKs National
Graphene Institute, used the same phraseology of killer
application when describing the future outlook for
graphene, commenting that while there are many areas of
development that are being explored, it remains uncertain what
is next for the nano material.
One area that holds a lot of possibilities for graphene is
energy storage, according to Ghaffarzadeh, who outlined
graphene technology, the market and its players in the Graphene
Live! 2014 opening keynote.
According to his presentation, supercapacitors, or electric
double-layer capacitors (EDLC) are one area where there is
great potential for graphene.
This technology stores energy by separation of a charge in a
so-called Helmholtz double layer at the interface between the
surface of a conductive electrode and an electrolyte.
Dr Paolo Bondavali, head of nanomaterials group at
Frances Thales Group, explained that graphene exhibits
several characteristics that make it a viable
Such characteristics include very high rates of charge and
discharge, high life cycle (>100,000), good reversibility,
low toxicity of material used, high cycle efficiency, low
internal resistance making for a higher power output
and extremely low heating levels.
Several of these properties also mean graphene is being
considered as an alternative in lithium-ion (Li-ion) batteries,
which traditionally use graphite in anodes and cathodes.
Yet there are also drawbacks of using graphene in
supercapacitors, including the low amount of energy this type
of material can store and the fact that it requires
sophisticated switching equipment, Bondavali explained.
Ghaffarzadeh also outlined that while graphenes
properties make it a suitable electrode material for
electrochemical supercapacitors, the material faces stiff
competition from indium tin oxide (ITO).
The market is currently dominated by ITO, which is
well established, explained Ghaffarzadeh. But
graphene is positioning itself as an ITO alternative, he