Nature creates layered materials like bone and mother-of-pearl that become less vulnerable to blemishes as they grow. Now researchers have created a composite layered 2D material that is resistant to breakage and extremely stretchable, using biomimetic proteins modeled on squid ring teeth.
Researchers rarely report this interface property for bone and nose because it was difficult to measure experimentally.”
Melik Demiral, Lloyd and Dorothy Fohr Haq Chair in Biomimetic Materials and Director of the Center for Advanced Fiber Technologies, Penn State
Composite 2D materials are composed of atom-thick layers of a rigid material, such as graphene or an MXene -; Usually a transition metal carbide, nitride or carbonitride -; To glue the layers together separated by layers of something. Whereas graphene or MXene has bulk properties in large part, the strength of 2D composites comes from the interfacial properties.
“Since we are using an interfacial material that we can modify by repeating the sequences, we can fine-tune the properties,” Demiral said. “We can make it very flexible and very strong at the same time.”
He notes that the materials may also have unique thermal conduction arrangements, or properties, that allow heat to dissipate more strongly than 90 degrees in one direction. The results of this work were published today (25 July) in Proceedings of the National Academy of Science,
“This material would be great for insoles for running shoes,” Demiral said. “It can cool the foot and the insole won’t break from repeated flexing.”
These 2D composites can be used for flexible circuit boards, wearable devices, and other devices that require strength and flexibility.
According to Demiral, traditional continuum theory doesn’t explain why these materials are both strong and flexible, but simulations demonstrated that interface matters. What clearly happens is that with a high percentage of the material composed of the interface, the interface breaks in places when the material is under stress, but the material does not break completely.
“The interface breaks down, but the content doesn’t,” Demiral said. “We expected them to become obedient, but suddenly it’s not only obedient, but super stretchy.”
Others who worked on the project as at Penn State were Mert Wurrell, postdoctoral fellow; Tarek Majeed, Postdoctoral Fellow; Oguzan Kolak, graduate student; and Reginald F. Hamilton, associate professor in engineering science and mechanics.
Also working on this research were Dong Li, and Huajian Gao, Professor of Mechanical and Aerospace Engineering, both at Nanyang Technological University, Singapore.
Defense Advanced Research Projects Agency; Army Research Office; Nanyang Technological University; and the Science, Technology and Research Agency, Singapore supported this work. Computations were performed at the A*STAR Computational Resource Center, National Supercomputing Center, Singapore.