Mathematical model creates extremely strong 3D graphene

MIT researchers have designed a strong and lightweight three-dimensional form of graphene.

With a sponge-like configuration, it is up to 10 times as strong as steel – at a fifth of its density. Until now, researchers had struggled to translate the two-dimensional strength of graphene into a three dimensional structure. This was solved by the MIT researchers analysing the material on an atomic level within the structure.

Dr Markus Buehler, head of MIT’s Department of Civil and Environmental Engineering and co-author of the study, said: “What we've done is realise the wish of translating these 2-D materials into three-dimensional structures.”

Although two-dimensional materials possess both exceptional strength and unique electrical properties, their thinness prevents them being used in vehicles, buildings or devices. Using heat and pressure, small flakes of graphene were compressed forming gyroids – similar to a Nerf ball full of holes. These structures resemble diatoms, small microscopic creatures that have a large surface area compared to their volume.

It is not possible to recreate 3D graphene on a large scale using conventional manufacturing methods, so the team created 3D examples from plastic on a larger scale for testing purposes. They also created a mathematical model that very closely matched their experimental results.

The scientists believe it may be possible to use polymers or metal particles as templates, before coating them with graphene using chemical vapour deposition before applying heat and pressure. The polymer or metal could then be either physically or chemically removed, leaving graphene behind in a three-dimensional state.

Possible uses of the geometry discovered by the researchers include concrete for a bridge, allowing for similar strength at a far lesser weight or use in filtrations systems, both for water or chemical processing. The study was published in Science Advances.