Graphene is mainly found in the form of a two-dimensional structure, which does not allow using a number of its advantages - strength, lightness, electrical and thermal conductivity. Scientists at MIT recently developed a 3D version of graphene that is 10 times stronger than steel in strength. Now, their colleagues at Rice University have used carbon nanotubes to harden graphene foam. The resulting 3D material can withstand 3, 000 times its own weight and can be shaped into almost any shape.
Much like conventional metal reinforcement reinforces concrete, graphene foam is structured around carbon nanotubes in several concentric layers. Scientists have previously created 3D graphene foam and used nanotubes to reinforce graphene in 2D. Now they have managed to combine foam and graphene reinforcement into one whole.
The researchers mixed the nanotubes with a powdered nickel-sugar catalyst to produce carbon. The dried granules of the substance were then compressed into a screw-shaped tooling. The carbon and sugar were turned into graphene through the process of chemical deposition. After removing the nickel residues, pure carbon remained.
Studies have shown that graphene foam with nanotube reinforcement, even under a load of 8, 500 times its weight, deforms by only 25%. As already mentioned, products of almost any shape can be made from it. One of the first application experiments was the electrodes of lithium-ion capacitors, which showed high mechanical and chemical stability.