Advanced materials with low density and high strength have transformative impacts in construction, aerospace and automobile industries. These materials are realized with integrating well-designed modular building units into interconnected structures. Here, we present a hierarchical design strategy to demonstrate a new class of carbon-based closed-cellular structures (CCS). The building units are prepared by a multi-scale approach starting from functionalized graphene oxide nanosheets, leading to the microfluidic synthesis of solid-shelled bubbles with shape diversity at the micro-scale, followed by the assembly into meso-scale 3D structures. Subsequently, these are transformed into self-interconnected and structurally-reinforced CCS, resulting in graphene lattices with rhombic dodecahedral honeycomb structures at the centimeter-scale. The 3D suprastructure simultaneously exhibits the Young’s modulus above 300 kPa while retaining a light density of 7.7 mg/cm3 and the elasticity against up to 80% of the compressive strain. The fabricated 3D CCS opens a new pathway for designing lightweight, strong, and superelastic materials.

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