A group of researchers from MIT has developed a new type of graphene that not only is 10-times stronger than steel, but also 95% less dense.
In the study, originally published in the journal Science Advances, lead researcher Markus Buehler and his colleagues exhibited how fusing and compressing graphene flakes results in the birth of the new material while mitigating some of the known weaknesses of graphene.
Graphene has long had the reputation of being the strongest of all known materials. However, the kind of strength it displays in its 2D form doesn’t carry over when it is formed in 3D. The study by Buehler and his team found a way to get around that problem.
Apparently, the researchers figured out that the solution to the aforementioned problem lies in the way the material is used. That understanding prompted them to develop a new, previously unseen geometric pattern which further proved that other lightweight and strong materials could also be manipulated by tweaking their geometric features.
Worth noting, earlier studies also explored different avenues within the current understanding of graphene’s properties to find a way to strengthen the material artificially, albeit unsuccessfully. Taking a cue from the less-than-ideal results of the earlier studies, Buehler’s team decided to analyze graphene down to the individual atoms within the structure. This approach eventually paved the way for a new mathematical framework that fell in line with the observations in their lab tests.
By regulating the heat and pressure applied on the material, the researchers managed to compress graphene flakes, creating a stable and strong structure similar to the microscopic creatures called diatoms. The structure, with its relatively much higher surface area compared to the volume, was found to be much stronger than initially anticipated.
“Once we created these 3D structures, we wanted to see what’s the limit – what’s the strongest possible material we can produce,” said Zhao Qin, one of the study authors.
The researchers developed different types of 3D models and put all of them to test. Following the simulated studies, they zeroed in on the graphene sample that displayed 10-times the strength of steel, but only 5% of its density.