Nature creates layered substances such as bone and nacre that become less susceptible to defects as they grow. Researchers are now using biomimetic proteins patterned on the teeth of squid rings to create break-resistant, highly stretchable composite layered 2D materials.
Researchers rarely reported this interfacial property between bone and nacre because it was difficult to measure experimentally. “
Melik Demirel, Lloyd and Dorothy Fail Hack Chair, Biomimetic Materials, Director of Pennsylvania State Advanced Textile Technology Center
Composite 2D materials consist of atomic-thick layers of hard materials such as graphene and MXene-; usually carbides, nitrides, or carbonitrides of transition metals-; separated by some layer, Glue the layers together. Large chunks of graphene or MXene have bulk properties, but the strength of 2D composites comes from interfacial properties.
“We use interface materials that can be changed by repeating the sequence, so we can fine-tune the properties,” says Demirel. “We can make it very flexible and at the same time very strong.”
He also pointed out that the material has its own heat transfer regime or properties and can diffuse heat in one direction more than 90 degrees.The result of this work is today (July 25th) Minutes of the National Academy of Sciences..
“This material is great for running shoe insoles,” says Demirel. “It was able to cool the foot and repeated flexions did not break the insole.”
These 2D composites can be used for flexible circuit boards, wearable devices, and other equipment that requires strength and flexibility.
According to Demirel, traditional continuum theory does not explain why these materials are strong and flexible, but simulations have shown that interfaces are important. Obviously, when the proportion of material that makes up an interface is high, stress on the material causes the interface to break in place, but not the entire material.
“The interface breaks, but the material doesn’t,” Demirel said. “We expected them to comply, but suddenly they are not only compliant, but also very elastic.”
Another person working on this project from Pennsylvania State University was postdoctoral fellow Mert Vural. Tarek Mazeed, postdoc. Oguzhan Colak, graduate student. Reginald F. Hamilton, Associate Professor of Engineering Science and Mechanics.
Also working on this research are Don Lee of Nanyang Technological University in Singapore and Hua Jian High School, a professor of mechanical engineering and aerospace engineering.
Defense Advanced Research Projects Agency; Army Research Institute; Nanyang Technological University; Agency for Science, Technology and Research, Singapore supported this work. The calculations were performed at the A * STAR Computational Resource Center in Singapore’s National Supercomputing Center.