This new silver application may push demand, prices even higher
Silver has had a great year so far, with prices hitting last month their largest monthly gain since August 2013 and peaking near $18 last week.
And while prices have dropped a bit since then, they could get a major boost if a new research published this week proves what it claims — that silver could be the key main ingredient in the making of the highly anticipated flexible touchscreens.
A team of researchers fro the English University of Surrey published a paper this week, which describes how silver nanowires are the ideal material for flexible touchscreen technologies.
Currently, touchscreen devices like those of smartphones and tablets rely on electrodes made from indium tin oxide (ITO), a material that is expensive to source and process, as well as very brittle.
But the team of scientists, led by Professor Alan Dalton and in collaboration with M-SOLV Ltd, a touch-sensor manufacturer based in Oxford, found that silver nanowire seem be the strongest competitor to alternative materials explored in recent years, such as graphene, carbon nanotubes and random metal nanowire films.
The experts explain that silver nanowires are over a thousand times thinner than a human hair and form an interconnected conductive network.
“Our research hasn’t just identified silver nanowires as a viable replacement touchscreen material, but has gone one step further in showing how a process called ‘ultrasonication’ can allow us to tailor performance capabilities,” said Matthew Large, first author on the research, said in a statement.
“By applying high-frequency sound energy to the material we can manipulate how long the nanosized ‘rods’ of silver are,” Large added. “This allows us to tune how transparent or how conductive our films are, which is vital for optimizing these materials for future technologies like flexible solar cells and roll-able electronic displays.”
In the course of their study, the team produced a fully operating five-inch multi-touch sensor like the ones typically used in smartphone technology. They found it performed comparably to one based on ITO, but used significantly less energy to produce.
So, in addition to performing well, silver nanowires can be produced in a less energy-intensive manner, proving to be a green alternative, too.
“The fact that the nanowire films are processed by the same laser techniques as ITO makes the transition from ITO to nanowires really straightforward. It won’t be long before we are all using nanowires in our electronic devices,” said Maria Cann, a technologist from M-SOLV.
The team, now based at the University of Sussex is now looking to develop the scalability of the process to make it more industrially viable.
Only around 30% of global output is from primary silver mines, less than the contribution of by-product production at zinc and lead mines where a number of mine closures are in the offing.
The bulk of silver usage is also in industrial applications including alloys, electronics, photovoltaic and for the production of ethylene oxide.