New super-strong graphene materials are expected to replace carbon fiber

An international team of Chinese and American scientists has developed a super-tough, highly conductive graphene composite film that can be produced at a lower cost at room temperature and is expected to replace the widely used carbon fiber materials.

Published in the latest issue of the Proceedings of the National Academy of Sciences, the team of Prof. Cheng Qunfeng from Beijing University of Aeronautics and Astronautics and the team of Ray Bowman of the University of Texas at Dallas were inspired by the mechanical structure of natural mother-of-pearl to prepare microscopic The structure is similar to the ordered layered graphene structure of mother-of-pearl.

Cheng Qunfeng told the Xinhua News Agency that it was time-consuming and laborious to stack graphene microcontrollers into thicker macro materials. For example, to prepare a graphene film of human hair thickness, it is necessary to stack 150,000 layers of single-grain graphene, and the interface between the layers is weak, and the mechanical properties are poor.

The mother-of-pearl has high strength and high toughness mechanical properties, mainly due to the internal layered structure and rich interfacial interactions such as ionic bonds, covalent bonds and hydrogen bonds. The researchers used chemical preparation rather than mechanical stacking to make this material. They borrowed the layered connection of mother-of-pearl and introduced the graphene nanosheets firmly by stitching together the cross-linking molecules with different bonds such as covalent bonds and conjugated bonds between the graphene oxide layers. A tough, integrated, highly conductive graphene film.

Cheng Qunfeng said that the tensile strength of this film material is 4.5 times that of ordinary graphene film, and the toughness is 7.9 times that of the latter.

According to the researchers, the preparation conditions of traditional carbon fiber materials need to exceed 2500 degrees Celsius, but the new materials can be prepared at room temperature below 45 degrees Celsius, the strength is comparable to carbon fiber composite materials , the cost is lower, and it is easy to achieve commercial scale preparation.

Cheng Qunfeng said that this low-cost, low-temperature, high-performance multi-functional graphene nanocomposite has broad application prospects in aerospace, automotive, flexible electronic devices and other fields.

The author of the paper, Bowman, said that the film is expected to eventually replace the carbon fiber composite materials used in aircraft and automobiles.