Aerogels are a recent class of materials where the liquid part of the gel is replaced by air. This makes for a very light material, so light that it is called “liquid smoke”.
Researchers at the Lawrence Livermore National Laboratory have managed to create an aerogel made of graphene. The aerogel is made through 3D printing of the structure, as shown in the image.
It is not the first time that graphene aerogels are made but in the previous attempt the resulting structure was not uniform, had holes and clumps. This decreases its effectiveness.
Why are regular structures so important? In many electrical and chemical reactions what matters is the surface of objects. Electrons, particularly at high frequency, move to the surface of the conductor and chemical reactions are not just taking place at the surface of the container, they can also be stimulated (catalyzed) by the particular “atomic” shape of the surface.
Hence the interest in creating graphene structures having a large surface so that more can be accomplished.
As you can see in the image, the “cube-like” structure is printed in such a way to leave plenty of gaps between the graphene “wire”. This provides a very big surface area and at the same time the graphene is a good conductor with interesting mechanical properties: it is at the same time stiff and resistant and can be squeezed up to 90% of its volume –supercompressibility- (of course this would kill most of the surface area) and will bounce back to its original shape when compression forces are removed.
Researchers hope this 3D printing process may create better batteries, better sensors and customized sieves. The 3D process can be customized to create the desired porous structure . This, as an example, can allow the production of highly effective water filters for desalinization.
Just another example of the possibility we have today in creating materials with desired properties working at the computer till we are satisfied and then printing it out as we used to print a drawing…