Researchers from Kansas State University, the University of Buffalo, and the State University of New York have teamed up to create a lightweight 3D printed material: an aerogel based on graphene.

The discovery could lead to greater use of graphene along a wider range of applications. The value of graphene, with its pliability, conductive properties and strength, is widely known, but the material can be difficult to manipulate in 3D printing technology.

Lighter-than-air 3D printed graphene aerogel. Image source: The University at BuffaloLighter-than-air 3D printed graphene aerogel. Image source: The University at BuffaloUntil now, to create 3D graphene, a polymer has been introduced during the process, which is later removed using chemicals. In an aerogel application, however, the use of chemicals destroys the original structure, rendering the part useless.

To overcome that challenge, the research team mixed graphene oxide (graphene that has additional oxygen atoms) with water, then deposited the layers on a surface at -25 C. Each layer froze, allowing the researchers to construct the aerogel with only ice as its support structure.

Once the structure was created, it was submerged in liquid nitrogen to strengthen the hydrogen bonds. Next, the water was removed with a freeze-drying technique that left the structure intact. The result was densities that ranged from 0.5 kg per cubic meter to 10 kg per cubic meter. The lightest aerogel until now is about 0.16 kg per cubic meter.

By combining drop-on-demand 3D printing with freeze casting, the team developed a graphene aerogel with 3D overhang structures. With its superelastic and high electrical conduction properties, the material could improve computer speed, battery power and find uses in a range of other applications.