Strong and Tough\nNacre-Inspired Graphene Oxide Composite\nwith Hierarchically Similar Structure

Abstract

We report a graphene oxide (GO)-based composite, featuring\nGO/cross-linking\nagent (CA) nanoparticles, inspired by a nacre-like hierarchical structure\npresent in nature. The as-prepared GO/CA composite was powdered to\nnanoscale particles and then mixed with pure GO to be GO/CA/GO (GCG)\ncomposite forming hierarchical GO/CA nanoasperities on the GO surface.\nThe strength and toughness of the nacre-inspired GCG composite films\nwere simultaneously improved by adjusting the nanoparticle concentration\nand hierarchical level of the GO-based films. Compared to pristine\nGO films and GO/CA composites, which exhibit a low level of hierarchy\nin their structures, the tensile strength and toughness of the GCG\ncomposites with higher hierarchy were enhanced 3.1 and 1.6 times and\n47.6 and 10.9 times, respectively. Furthermore, a plausible mechanism\nof increasing mechanical properties based on nanoscale asperities\nand homogeneous interactions between GO and CA has been discussed.