High-strength scalable graphene sheets by freezing stretch-induced alignment

Abstracct Efforts to obtain high-strength graphene sheets by near-room-temperature assembly have been frustrated by the misalignment of graphene layers, which degrades mechanical properties. While in-plane stretching can decrease this misalignment, it reappears when releasing the stretch. Here we use covalent and pi-pi inter-platelet bridging to permanently freeze stretch-induced alignment of graphene sheets, and thereby increase isotropic in-plane sheet strength to 1.55 GPa, in combination with a high Young's modulus, electrical conductivity and weight-normalized shielding efficiency. Moreover, the stretch-bridged graphene sheets are scalable and can be easily bonded together using a commercial resin without appreciably decreasing the performance, which establishes the potential for practical applications. Stretch-induced alignment of graphene sheets is frozen by sequential covalent and pi-pi bridging, leading to high in-plane isotropic strength of 1.55 GPa. The graphene sheets are fabricated at near room temperature and are scalable.

Automated summary

The study used covalent and pi-pi inter-platelet bridging to permanently freeze the stretch-induced alignment of graphene sheets, increasing the isotropic in-plane sheet strength to 1.55 GPa, while maintaining a high Young's modulus, electrical conductivity and weight-normalized shielding efficiency. The graphene sheets fabricated at near room temperature are scalable and can be easily bonded together using a commercial resin without significantly decreasing performance.