Synergistically toughening nacre-like graphene nanocomposites via gel-film transformation

The gold standard of natural nacre provides the inspiration for assembling bioinspired nanocomposites. Herein, the gel-film transformation method, a feasible and economical strategy, was applied to fabricate flexible, large-area, and hierarchical porous graphene oxide (GO)-based nanocomposites with excellent properties. In this study, the GO-polymer nanocomposite hydrogels could be transformed into nanocomposite films with hierarchically laminated structures via the evaporation self-assembly technique, followed by introduction of ionic cross-linking into the nanocomposite films. The obtained bioinspired nanocomposites, with synergistic effect originating from hydrogen bonds and ionic bonds, have an excellent tensile strength of 475.2 ± 13.0 MPa and a toughness of 6.6 ± 0.3 MJ m^-3, as well as a high electrical conductivity of 297.1 S cm^-1. Therefore, this type of strong integrated nacre-like graphene nanocomposites have great potential applications in aerospace and flexible supercapacitor electrodes.