In the near future, we could be turning greasy food waste into the strongest material on earth, thanks to a cheap and simple technology developed by Australian scientists.
Graphene, made from carbon, is just one atom thick, has an optical transparency of 97.3% and is the strongest material on Earth. It’s a material so super that Tony Stark chose it for his high-tech bulletproof and transparent face-plate in Marvel Comics’ Superior Ironman #2.
Graphene is also very useful in real life, able to do everything from improving battery performance in energy devices to developing water-purification membranes.
Though its potential has been recognised for decades, the high cost of producing quality, large-scale graphene has been a significant barrier to its commercialisation.
That barrier was surmounted this year, when CSIRO scientists based in Sydney, Australia, found a much cheaper, faster way to produce graphene than the traditional method.
The GraphAir breakthrough
Until now, graphene has been grown in highly-controlled environs using explosive compressed gases, a process requiring hours of operation at temperatures that can reach 1,000°C and extensive vacuum processing.
The CSIRO scientists, working with researchers from The University of Sydney, University of Technology Sydney (UTS) and Queensland University of Technology (QUT), developed an innovative low-cost solution to growing graphene using just two simple ingredients: soybean oil and ambient air.
In a single step, the new technology, dubbed GraphAir, transforms a natural, renewable precursor – in trials, it was soybean oil – into functional and highly controlled graphene films composed of one or a few layers, eliminating the need for such highly controlled environments.
When heat is applied in ambient air to the precursor, it breaks down into an array of carbon-building units essential for the synthesis of graphene.
“This ambient-air process for graphene fabrication is fast, simple, safe, potentially scalable, and integration-friendly,” asserts CSIRO’s Dr Zhao Jun Han, co-author of the paper published in Nature Communications in January 2017.
CSIRO scientist and co-author of the study, Dr Dong Han Seo, said, “Our GraphAir technology results in good and transformable graphene properties, comparable to graphene made by conventional methods.
A new use for waste cooking oils
The team has also been testing other renewable triglyceride (carbon)-containing precursors – including butter and even waste oils, such as those that might be drained from a fish-n-chip shop fryer or backyard barbecue – and has found that these can also be turned into graphene film.
“We can now recycle waste oils that would have otherwise been discarded and transform them into something useful,” Dr Seo says.
Potential applications: from solar power and sensors to water purification
“Our unique technology is expected to reduce the cost of graphene production and improve the uptake in new applications,” contends Dr Han.
GraphAir technology has the potential to deliver many new applications affordably, ranging from water filtration and purification to renewable energy, sensors and personalised healthcare and medicine.
Now that it’s worked out a low-cost method for producing graphene, CSIRO is looking to partner with industry to find new uses for graphene and commercialise its technology. Stay tuned.