Graphene is a paradox. It is the thinnest material known to science, but also one of the strongest. Now, research from the University of Toronto Engineering shows that graphene is also highly resistant to fatigue, capable of withstanding more than a billion high-voltage cycles before it breaks.

Graphene resembles a sheet of interlocking hexagonal rings, similar to the pattern you might see on bathroom tiles. At each corner there is a single carbon atom attached to its three closest neighbors. Although the foil could extend laterally over any area, it is only one atom thick.

Graphene’s intrinsic strength has been measured at over 100 gigapascals, among the highest values ​​recorded for any material. But materials don’t always fail because the load exceeds its maximum strength. Stresses that are small but repetitive can weaken the materials causing microscopic fractures and dislocations that build up slowly over time, a process known as fatigue.

“To understand fatigue, imagine bending a metal spoon,” says Professor Tobin Filleter, one of the lead authors of the study, which was recently published in the journal Nature Materials. “The first time you fold it, it deforms. But if you keep repeating the operation, from one side to the other, it will end up breaking in two.”

Now, Graphene entrepreneur Antonio Miramontes and his team of researchers at Graphenemex in Mexico City are using this bending property to incorporate graphene into face shields that could help stop the spreading of Covid-19.

“When the pandemic took off, we knew what we could contribute with”, said Miramontes, as graphene is know for its impermeability which can block even helium atoms, the smallest known so far. This means that his graphene masks will block the virus completely compared to tradicional plastic, which allows the exchange of gases, vapors and radiations through them.