Strong Graphene 3D Assemblies with High Elastic Recovery and Hardness

Abstract The rational design and construction of 3D graphene assemblies is a crucial step to extend the graphene properties for practical applications. Here, a novel interfacially reactive self‐assembling process is reported to prepare well‐organized 3D honeycomb‐like graphene assemblies with unique polygonal nanopores interconnected by silicon‐oxygen chemical bonds. The newly developed silicate‐bridged graphene assembly (SGA) exhibits an exceptionally high hardness of 13.09 GPa, outperforming all existing 3D graphene materials, while maintains high Young's modulus (162.96 GPa), elastic recovery (75.27%), and superb thermal stability (600 °C in air). The observed unusual merits are resulted from unique pore structure combining the mechanical stability of the trihedral‐nanopore structure and the deformability of the other polygonal nanopores. As a filling material, a merely 0.05% (w/w) addition of SGA could double the impact resistance of unsaturated resins (e.g., polyester). While SGA is attractive for various applications, including body armors, wearable electronics, space elevators, and multifunctional reinforcement fibers for automobiles, and aerospace vehicles, the novel liquid sodium–water interfacial reactive self‐assembling developed in this study could open avenues for further development of various well‐defined 3D assemblies from graphene and many other materials.