By Graham Pinn
The invention of plastics changed the world in the Twentieth Century, graphene a form of carbon, will do the same in the Twenty-first. It is light and very strong (estimated at up to 200 times stronger than steel) – strong enough to stop a speeding bullet! It is heat and electricity conducting, and is believed to be the future of electronics, with applications in computers, batteries, solar panels, sensors, and medical and military devices. A recent development has suggested the possibility that graphene can even produce its own low- energy output, coming from the motion of its molecules.
The problem has been how to economically manufacture it on a commercial scale. Carbon exists in nature in two forms, graphite (as in lead pencils) and the more exotic diamond; graphene does not exist in nature. There had been 70 years of speculation about the substance before it was finally produced by rudimentary processes in 2004; its discoverers, in UK, were subsequently awarded the Nobel Prize for physics in 2010. Its development has been the Holy Grail of technology.
Its original manufacture was far from simple. Starting with graphite, requiring a sheet of copper, very high temperatures, and an argon gas filled furnace, the end result was a 2- dimensional layer of carbon one molecule thick. In 2015 a Canadian process produced graphene nano-ribbons from methane. In the US its manufacture was improved using copper foil in a hydrogen atmosphere at room temperature. Graphite then became an in-demand item, the problem being, as with rare earths, China had most of it. New sources are now being developed in Canada, Mexico, Brazil and Madagascar; even the old Cornish tin mines are now being re-opened to mine graphite and lithium, impurities in the tin. Australia has its own supplies, with the purest resource in South Australia.
In 2017 the CSIRO invented a process using soy bean oil as the carbon source and nickel instead of copper; this has already been used commercially in Australia to produce a filter for water purification. As of 2019 production was still an expensive process, with cost estimated at $100 per Gram, and could be produced only in small volumes. That year, a new approach by RMIT used eucalyptus bark and projected a dramatic fall in costs to as little as 50 cents per Gram; using biological sources, however, has a disadvantage in reducing purity and efficiency. Numerous techniques are currently under investigation, using Plexiglas and sugar as the carbon source, even plant waste has been suggested; graphite supplies may be limited but any carbon-based source could theoretically be used.
Commercial supplies are still limited, in 2020 total production was estimated at 20,000 tons; by 2022 the graphene market was estimated to be worth over $400 million US, with 20 international and 17 Chinese companies involved; the market is expected to triple by 2027.
The EU has spent around US$1 billion since 2014, on R and D, involving 125 different organisations, its largest ever investment in R and D. There are several dozen companies in the US and Canada, working on its use in diverse areas such as ceramics, aerospace, electronics, medical applications, sports equipment and batteries. The UK has invested over $150 million, and has a purpose-built institute in Manchester, where graphene was first produced.
There are currently many production processes. In Australia, the Graphene Manufacturing Group (GMG) is expanding its production from methane; plasma technology has been used for 5 years to split the natural gas into carbon (as graphene) and hydrogen, and a new, modular, production facility is being developed at Redlands. Eventually, 20 production units are planned at this site. Another process, developed by First Graphene, near Perth, uses the more traditional high purity graphite electrochemical exfoliation method.
With increasing importance of storage of renewable energy, graphene is proving a more efficient and safer option than current lithium-based batteries; the latest development is a graphene enhanced lithium-ion car battery, being produced in Spain. Using another technology, Australian researchers are working on a graphene aluminium-ion battery; in February 2023, the Graphene Manufacturing Group received approval for commercial battery production at its site in Brisbane. Rio Tinto has invested in the company, to develop batteries for its mining trucks and energy storage.
The battery advantages are a rapid charging capability of a few minutes, and a 60% increase in capacity; unlike the original lithium-ion, heat is not produced, so the current battery fires may not be a problem and batteries do not need the mix of expensive rare earths, required for the traditional alternative. Opportunities for battery expansion into other areas, such as drones, even mobile phones, are appearing. The current main graphene use is expected to be in the electronics sphere; it is ten times more efficient than semi- conductors and does not heat up.
Production costs, still currently between US$100 and $400, per gram, are falling at around 12% per annum, but demand exceeds supply and new uses are continually being discovered; bullet proof body armour and anti-corrosion paint being the latest. Future production is estimated at around 30,000 tons by 2030, but commercial production is difficult and expensive. The other big problem is assessing the quality of the product, this can vary enormously with different production methods; currently there are no international standards.
An important use for Australia could be to desalinate water, currently an expensive process. It can also be added to other materials such as carbon fibre, fibre glass and concrete, to improve strength and heat resistance; unlike plastics, its other advantage is that it will not pollute the environment. One day, because it is light and strong, steel and glass could be replaced and even cars and planes be constructed from graphene.
The next step requires development of an industrial-scale manufacturing process; when achieved, the uses are enormous; a growth rate of 30% annually is anticipated. Plastic use will decline and, with it, associated environmental pollution problems. The next question then will be – will it also pollute the environment? Animal and early human studies have suggested that, unlike plastic nano-particles it will be safe; time will tell.
Graham Pinn was a medical doctor for 50 years and has worked in 10 different countries throughout the world. “In retirement there is time to fight the good fight against global warming misinformation, before the lights go out.”
This is very interesting! Is there any leads to more information on this subject?
I have known for many years that graphite is common in many areas of the Earth’s crust, not only because a gold mine I was testing equipment at had a serious problem with graphite in their ore that compromised their recovery processes.
What about the claim that traces of Graphen have been detected as a potentially dangerous inclusion in the so called anti-Covid vaccinations?