Wet-Chemical Assembly of 2D Nanomaterials into Lightweight, Microtube-Shaped, and Macroscopic 3D Networks

Despite tremendous efforts toward fabrication of 3D macro-structures of 2D materials, the existing approaches still lack sufficient control over microscopic (morphology, porosity, pore size) and macroscopic (shape, size) properties of the resulting structures. In this work, a facile fabrication method for the wet-chemical assembly of carbon 2D nanomaterials into macroscopic networks of interconnected, hollow microtubes is introduced. As demonstrated for electrochemically exfoliated graphene (EG), graphene oxide (GO), and reduced graphene oxide (rGO), the approach allows for the preparation of highly porous (> 99.9%) and lightweight (< 2 mg cm-3) aeromaterials with tailored porosity and pore size as well as tailorable shape and size. The unique tube-like morphology with high aspect ratio enables ultra-low percolation threshold graphene composites (0.03 S m-1, 0.05 vol.%) which even outperform most of the CNT-based composites, as well as highly conductive aero-networks (8 S m-1, 4 mg cm-3). On top of that, ...