Graphene is considered one of the most important breakthroughs in material science since its discovery. This “wonder material” was widely overhyped, and still hasn’t lived up to its potential. We can now see more concrete and realistic applications hitting the market — not those out of this world promises like the space elevator. What if we could cut down carbon emissions from cement production by 20% and make cheaper and more powerful EV batteries using graphene? Is graphene finally starting to deliver on the promise? 

Graphene is a hexagonal honeycomb lattice made up of a single layer of carbon atoms. It’s a physical form of carbon with a molecular bond length of 0.142 nanometres and each atom is connected to three more around it by bonds that are very tight. Graphene essentially has only two dimensions, and if we stack several layers of it on top of each other, we can turn it into graphite.

The “wonder material,” as graphene is often called, is one of the thinnest materials that we know of and the lightest compound ever discovered (weighing around 0.77 mg/m²). Graphene is also one of the strongest compounds (between 100-300 times stronger than steel), as well as one of the best heat and electricity conductors at room temperature (it has an electrical conductivity 70% higher than copper). You can see why so many people hailed it as the next technological revolution.

Research on graphene started in 1947 by physicist Philip R. Wallace, but it was only discovered by researchers from the University of Manchester in the United Kingdom in 2004 by Geim and Novoselov. They used a sticky tape to peel flakes from a lump of graphite, separating the layers until they were only one atom thick. The discovery was so revolutionary that they were awarded the Nobel Prize in 2010.

 

Although it has all of the characteristics to be an excellent material in theory, manufacturing defect-free graphene is often too expensive. Its price can vary a lot based on the manufacturing conditions, and the methods for the mass-production of this material haven’t been cost-effective.It’s something that often happens to discoveries in the lab. Bringing it to market and producing it cheaply at scale can be extremely difficult.

 

Even though the best physical properties of graphene can be achieved using the peeling method proposed by Geim and Novoselov, it isn’t the most effective and feasible way to produce tons of graphene. Chemical vapor deposition (CVD) is one of the main processes utilized to produce graphene. This procedure consists of synthesizing graphene on a substrate, often copper foil, but it’s still a challenge to produce long sheets of this material at scale.

However, one example of a partnership trying to push this boundary is the joint venture formed between the Chinese company, Hangzhou ­Cable Co, and the University of New South Wales that’s trying to manufacture graphene power cables. The cables could reduce electricity leakages, lowering electricity costs and carbon emissions while improving the quality of grid transmission. The technology developed by the university could save about 275 TWh in theory. While that’s very interesting, it has yet to come out of the lab.

Because graphene is strong, light, and an outstanding heat conductor, it can be a great material for producing heat sinks or heat dissipation films. Huawei’s latest smartphones, for example, have adopted graphene-based thermal films and the British company Graphene Lighting is producing LED lights using graphene as a thermal dissipation solution.

Meanwhile the Australian-based company First Graphene has its sights on the cement and concrete industry. Cement accounts for between 8-10% of CO2 emissions, which explains why it was a target for CO2 reduction at COP26. Forty of the world’s biggest cement and concrete companies have banded together to speed up the transition to greener concrete by pledging to reduce CO2 emissions by 25% by 2030. 

Clinker is used as the binder of cement. In this process, huge amounts of electricity are spent for every ton of clinker produced, about 800-900 kg of CO2 per ton. First Graphene is tackling the final grinding step, where graphene can improve the efficiency of the cement grinding process. Graphene reduces the surface energy forces that cause agglomeration, or clumping, of the newly fractured cement particles.

To do this, they produce graphene based on electrochemical exfoliation, in which graphene is obtained from graphite when a voltage is applied to it. Instead of using tape to rip off layers of graphene, you’re using electricity to shed off layers of graphene. It basically sheds layers of graphene one at a time. They can produce graphene platelets with sizes between 5 and 70 microns, which can then be easily dispersed into materials … like concrete.

Adding just a small amount of their graphene product, PureGRAPH® AQUA (as low as 0.01% of the total concrete mix) to concrete improves tensile and compressive strength, also reducing weight and the chances of cracking. In my conversation with the company they explained how these improvements happen:

“…Graphene is a nanoscale reinforcement – like steel reinforcement bar but at the atomic level. The graphene can permeate the cement gel and stop cracks from developing on the nanoscale…” -First Graphene

According to a case study made by the company, when tested to international standard methods, PureGRAPH increases the compressive strength of concrete by 34% and tensile strength by 27%. On top of that, it extends the life of reinforced concrete structures because it avoids corrosion and also reduces clinker by 20%. This is where that CO2 reduction comes into play because of how it helps with clinker. CO2 emissions can be reduced by 18% -20%. Hopefully, as time matures the commercial applications of this mechanical miracle, we’ll be seeing it making a big change for the better.