Bridging In-Plane Order to Macroscopic Isotropic Ultralight MXene-Graphene Aerogels

Precise nanosheet organization across length scales remains a challenge in translating the intrinsic properties of two-dimensional (2D) materials into macroscopic porous architectures. Extending in-plane nanosheet order to long-range, three-dimensional (3D) frameworks without structural collapse has been elusive. Here, we report an ultralight MXene-graphene aerogel that exhibits isotropic nanosheet organization spanning from the nanoscale to macroscopic porous networks. This architecture is realized through alginate-induced liquid-crystalline assembly coupled with rapid ice-nucleation-driven compaction. The isotropic framework homogenizes capillary stresses during drying, enabling ambient-pressure fabrication of aerogels with an ultralow density of 9.0 mg cm^{- 3}. Continuous long-range, in-plane isotropic stacking of nanosheets enables efficient electron transport along the pore walls, resulting in enhanced electromagnetic interference (EMI) shielding performance. This work establishes a general strategy for constructing porous multiscale isotropic nanosheet architectures.